Filed Pursuant to Rule 424(b)(3)
                                                      Registration No. 333-32772

                                     [LOGO]

                     THIRD SUPPLEMENT DATED JUNE 1, 2001 TO
                         PROSPECTUS DATED APRIL 17, 2000

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Please read this Third Supplement in conjunction with the Prospectus dated April
17, 2000,  which was filed as part of our  Amendment  No. 1 to the  Registration
Statement On Form S-3 (Registration No. 333-32772) filed with the Securities and
Exchange  Commission on April 14, 2000 and declared  effective on April 17, 2000
(the "Original  Prospectus"),  as  supplemented  by the First  Supplement to the
Original  Prospectus  dated September 5, 2000 (the "First  Supplement")  and the
Second  Supplement to the Original  Prospectus dated April 27, 2001 (the "Second
Supplement").

A  copy  of the  Original  Prospectus,  the  First  Supplement  and  the  Second
Supplement are attached to this Third Supplement.

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     This Third Supplement (the "Third  Supplement")  modifies,  supplements and
amends the Original  Prospectus,  the First Supplement and the Second Supplement
with  respect to the offer and sale of shares of our Class A Common stock by the
selling stockholders named in the Original Prospectus.

                ADVANTAGE AND KOCH HAVE CONVERTED OR SOLD ALL OF
                  THEIR SHARES OF OUR SERIES D PREFERRED STOCK

     In May 2001, we were informed by Advantage Fund II Ltd and Koch  Investment
Group, Ltd., two of the selling  stockholders named in the Original  Prospectus,
that  they  had  converted  and/or  sold  all of their  shares  of our  Series D
convertible  preferred  stock. In addition,  Advantage and Koch have informed us
that  they have sold  shares  of our  Class A common  stock  issued to them upon
conversion  of  their  shares  of our  Series C  preferred  stock  and  Series D
preferred  stock.  We are  supplementing  the  Selling  Stockholder  information
contained in the Original  Prospectus to reflect prior resales,  conversions and
sales of Series D preferred stock and resales of Class A common stock by each of
Advantage and Koch.  Certain of the shares of our Class A common stock issued or
issuable upon conversion of the shares of our Series D preferred stock that were
sold by Advantage and Koch are being  registered  for resale by the purchaser of
such  shares of  Series D  preferred  stock  under  the  registration  statement
relating to this Supplement, Registration Statement No. 333-32772. The remaining
shares of our Class A common stock issued or issuable  upon  conversion  of such
shares  of Series D  preferred  stock are  being  registered  for  resale by the

purchasers of such shares under  another  registration  statement,  Registration
Statement  No.  333-60424.  As  a  result,  such  purchasers  shall  be  selling
stockholders in the registration statement relating to this Supplement.

     The following  table sets forth for  Advantage,  Koch and each purchaser of
shares of Series D preferred  stock sold by Advantage and Koch,  all of whom are
selling stockholders, (a) the name of the selling stockholder, (b) the number of
shares of our Class A common stock owned by the selling  stockholder  before the
offering (in some cases,  as noted in the  footnotes  to the table,  some or all
shares underlie or otherwise relate to the Series D preferred stock and warrants
held by the selling stockholder),  reflecting transfers through the date of this
Third  Supplement,  (c) the number of shares of our Class A common stock offered
by the selling  stockholder  under this prospectus,  (d) the number of shares of
our Class A common stock that will be owned by the selling stockholder  assuming
that all  shares  of our Class A common  stock  registered  hereby or  otherwise
registered on that stockholder's  behalf are sold, and (e) the percentage of our
outstanding  shares of Class A common  stock that those  remaining  shares  will
represent.  Each  selling  stockholder  is a party to, or  otherwise  has rights
under,  an  agreement  by which we agreed to register  its shares of our Class A
common stock.  Registration  of these shares enables the selling  stockholder to
sell  the  shares  from  time  to time  in any  manner  described  in  "Plan  of
Distribution" in the Original Prospectus, but does not necessarily mean that the
selling stockholder will sell all or any of the shares.



                                                                                                     PERCENTAGE OF
                                          NUMBER OF                                                OUTSTANDING CLASS
                                           SHARES                               NUMBER OF SHARES     A COMMON STOCK
                                        BENEFICIALLY                              BENEFICIALLY        BENEFICIALLY
                                        OWNED BEFORE     NUMBER OF SHARES TO      OWNED AFTER         OWNED AFTER
NAME OF SELLING STOCKHOLDER               OFFERING      BE SOLD IN OFFERING(4)      OFFERING            OFFERING
---------------------------               --------      ----------------------      --------            --------
                                                                                            
Koch Investment Group Ltd.               102,870 (1)            40,370                   --                --

Advantage Fund II Ltd.                   193,520(2)            131,020                   --                --

Harmonic Associates LP                   998,861(3)(5)         534,491                   --                --

The Alan Gelband Company
Defined Contribution Pension
Plan & Trust                             199,722(5)            106,898                   --                --

The Gabriella L. Gross Trust B(6)        175,303(7)             80,181               25,474               (8)

The Elizabeth Gross Trust A(6)           175,303(7)             80,181               25,474               (8)


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(1)  Consists of (a) 40,370  shares  issuable  upon the exercise of our warrants
     related to the  issuance  of our Series C preferred  stock;  and (b) 62,500
     shares issuable upon the exercise of warrants issued upon the redemption of
     certain of our secured  convertible  notes,  which  shares were  previously
     registered for resale under Registration Statement No. 333-41096.

(2)  Consists  of (a)  70,465  shares  issued  upon  conversion  of our Series C
     preferred  stock  and  60,555  shares  issuable  upon the  exercise  of our
     warrants  related to the issuance of our Series C preferred  stock; and (b)
     62,500  shares  issuable  upon the  exercise  of  warrants  issued upon the
     redemption of certain of our secured  convertible  notes, which shares were
     previously   registered  for  resale  under   Registration   Statement  No.
     333-41096.

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(3)  Pursuant  to the  terms  of the  Series  D  preferred  stock  held  by this
     stockholder, the Series D Preferred Stock is convertible by any holder only
     to the  extent  that the number of shares of Class A common  stock  thereby
     issuable  would not exceed  4.999% of the then  outstanding  Class A common
     stock as determined  in accordance  with Section 13(d) of the Exchange Act.
     Accordingly,  the number of shares of Class A common stock set forth in the
     table for this selling  stockholder exceeds the number of shares of Class A
     common stock that this selling  stockholder  could own  beneficially at any
     given time through its ownership of the Series D preferred  stock.  In that
     regard,  beneficial  ownership of this selling stockholder set forth in the
     table is not  determined in  accordance  with Rule 13d-3 under the Exchange
     Act.

(4)  The  actual  number  of  shares  of Class A common  stock  offered  in this
     prospectus  and  included  in the  registration  statement  of  which  this
     prospectus is a part includes  such  additional  number of shares of common
     stock  as may be  issued  or  issuable  upon  conversion  of the  Series  D
     preferred stock,  exercise of any of our warrants or otherwise with respect
     to the Class A common stock by reason of any stock split, stock dividend or
     similar transaction  involving the common stock in accordance with Rule 416
     under the Securities Act.

(5)  These shares are issued and/or issuable upon the conversion of our Series D
     preferred stock. All shares  beneficially owned by this selling stockholder
     not being  registered for resale  hereunder are being registered for resale
     under Registration Statement No. 333-60424.

(6)  The  beneficiary  of this  trust is the  daughter  of Irwin L.  Gross,  the
     chairman of our board of directors and our chief executive officer. Each of
     these daughters is also the beneficiary of a custodial account of which Mr.
     Gross' wife is custodian holding 4,500 shares of Class A common stock. Each
     such trust disclaims  beneficial ownership of any shares beneficially owned
     by the other such trust or Mr. Gross or deposited in either such  custodial
     account and no shares so owned or so  deposited  are included in any number
     of shares disclosed in this table with respect to each such trust.

(7)  Consists of (a) 149,829  shares issued and/or  issuable upon the conversion
     of our Series D  preferred  stock and (b)  25,474  shares of Class A common
     stock. All shares  beneficially  owned by this selling  stockholder  issued
     and/or  issuable upon the  conversion  of our Series D preferred  stock not
     being registered for resale hereunder are being registered for resale under
     Registration Statement No. 333-60424.

(8)  Less than 1%.

         WE HAVE RECEIVED NOTICE OF DELISTING FROM NASDAQ REGARDING OUR
                     FAILURE TO MEET MAINTENANCE STANDARDS.

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     We have received a Nasdaq Staff  Determination  on May 23, 2001  indicating
that we fail to comply with the net tangible  assets  requirement  for continued
listing set forth in Marketplace Rule 4450(a)(3), and that our shares of Class A
common  stock are,  therefore,  subject to  delisting  from the Nasdaq  National
Market.  The  letter  noted  that we also do not  meet  alternative  maintenance
requirements  under  Nasdaq  National  Market  Maintenance  Standard  2. We have
requested a hearing before a Nasdaq Listing  Qualifications  Panel to review the
staff  determination.  By letter dated May 30, 2001, Nasdaq informed us that our
hearing is  scheduled  for June 28,  2001.  This letter  indicates  that at this
hearing  we will be  required  to  address  our plan to regain  compliance  with
certain  quantitative  maintenance criteria of the Nasdaq National Market and to
demonstrate  our ability to sustain  long term  compliance  with all  applicable
maintenance criteria.  Delisting of our securities is stayed pending issuance of
a written  determination by the panel.  There can be no assurance the panel will
grant our request for continued listing.

     We also  received a letter  dated May 2, 2001 from Nasdaq  stating that our
Class A common  stock had failed to  maintain a minimum  market  value of public
float of $5 million  over the  preceding  30  consecutive  trading days and as a
result  was not in  compliance  with  the  Nasdaq  National  Market  maintenance
standards.  The letter  states  that if at any time before  July 31,  2001,  the
minimum  market value of public float of our Class A common stock is at least $5
million  for a  minimum  of 10  consecutive  trading  days,  Nasdaq  staff  will
determine  if we  comply  with the  maintenance  standard.  If we are  unable to
demonstrate  compliance  with this  maintenance  standard  on or before July 31,
2001, our Class A common stock will be delisted,  subject to our right to appeal
to a Nasdaq  Listing  Qualifications  Panel.  The  letter  notes  that we may be
delisted before July 31, 2001 for failure to maintain  compliance with any other
listing requirement for which we are currently on notice or which occurs in that
period.

     Our Class A common  stock is listed  for  trading  on the  Nasdaq  National
Market under the symbol "GTLL".  A listed company may be delisted if it fails to
maintain  minimum  levels of  stockholders'  equity,  shares  publicly held, bid
price, number of stockholders or aggregate market value, or if it violates other
aspects of its listing agreement.  We currently do not satisfy certain continued
listing  standards.  We are seeking  additional capital and attempting to effect
other  equity  transactions  to, among other  things,  increase our net tangible
assets.  There can be no assurance that we will be able to raise this additional
capital,  or if we are  able to  raise  additional  capital  it will be on terms
satisfactory  to us, or to effect  other  equity  transactions  currently  under
consideration.  There can be no assurance  that any steps we take will enable us
to meet the criteria for continued  listing  relating to minimum market value of
public  float or minimum  bid price,  which  criteria  relate to market  factors
beyond our control.  If we fail to satisfy the criteria for  continued  listing,
our Class A common stock will be delisted.

     If our Class A common  stock is delisted  and we do not then  qualify for a
listing on a stock  exchange or for  quotation  on the Nasdaq  SmallCap  Market,
public trading,  if any, would  thereafter be conducted in the  over-the-counter
market in the so-called  "pink  sheets," or on the NASD's  "Electronic  Bulletin
Board." In this event, it may be more difficult to dispose of, or even to obtain
quotations  as to the price of, our Class A common stock and the price,  if any,
offered for our Class A common stock may be substantially reduced.

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     If our common stock is delisted from trading on the Nasdaq  National Market
and we do not then  qualify for a listing on a qualified  stock  exchange or for
quotation  in the Nasdaq  SmallCap  Market,  and the market  price of our common
stock is less than $5.00 per share,  subject to certain  exceptions,  trading in
our common stock would be subject to the requirements of Rule 15g-9  promulgated
under the  Securities  Exchange Act of 1934,  as amended (the  "Exchange  Act").
Under this rule,  broker/dealers  who recommend such securities to persons other
than established  customers and accredited investors (generally  institutions or
high-net   worth   individuals)   must  make  a  special   written   suitability
determination for the purchaser and receive the purchaser's written agreement to
a transaction prior to sale. The requirements of Rule 15g-9, if applicable,  may
affect the ability of  broker/dealers to sell our securities and may also affect
the ability of purchasers in this offering to sell their shares in the secondary
market.

     The Securities Enforcement Remedies and Penny Stock Reform Act of 1990 (the
"Penny Stock Rule") also requires  additional  disclosure in connection with any
trades involving a stock defined as penny stock (any non-Nasdaq  equity security
that has a market price or exercise price of less than $5.00 per share,  subject
to certain exceptions).  Unless exempt, the rules require the delivery, prior to
any transaction  involving a penny stock, of a disclosure  schedule  prepared by
the SEC  explaining  important  concepts  involving the penny stock market,  the
nature of such market, terms used in such market, the broker/dealer's  duties to
the  customer,   a  toll-free   telephone   number  for   inquiries   about  the
broker/dealer's  disciplinary  history and the customer's rights and remedies in
case of  fraud  or  abuse  in the  sale.  Disclosure  must  also  be made  about
commissions payable to both the broker/dealer and the registered representative,
and current quotations for the securities.  Finally,  monthly statements must be
sent disclosing recent price information for the penny stock held in the account
and information on the limited market in penny stocks.

       THE NETWORK CONNECTION HAS RECEIVED NOTICE OF DELISTING FROM NASDAQ
     REGARDING ITS FAILURE TO MEET MAINTENANCE STANDARDS WHICH SUBSTANTIALLY
      REDUCES THE MARKETABILITY OF OUR HOLDINGS IN THE NETWORK CONNECTION.

     The Network Connection has received a Nasdaq Staff Determination on May 25,
2001  indicating  that, due to (a) the staff's  concerns  regarding the residual
equity  interest of the  existing  listed  securities  holders,  (b) The Network
Connection's March 24, 2001 filing under Chapter 11 of the U.S.  Bankruptcy Code
as  set  forth  in  Marketplace  Rules  4330(a)(1)  and  (3),  (c)  The  Network
Connection's  having not yet  prepared  a plan of  reorganization  (The  Network
Connection  is not  obligated  to file a plan of  reorganization  until July 22,
2001,  subject to  extension)  and being unable to  determine  the effect on its
current shareholders and (d) The Network Connection's failure to demonstrate its
ability to sustain compliance with all requirements for continued listing on the
Nasdaq  Stock  Market,  its shares of common  stock are,  therefore,  subject to
delisting from the Nasdaq  SmallCap Market at the opening of business on June 4,
2001. In addition,  the staff noted that because The Network  Connection had not
filed  its  Form  10-QSB  for  the  period  ended  March  31,2001,  the  staff's
determination  to  delist  was also  based on this  filing  delinquency  and its
trading symbol was changed from "TNCXQ" to "TNCQE".  The Network  Connection has
not filed its  quarterly  report on Form  10-QSB for the period  ended March 31,
2001 because by letter dated May 4, 2001 it requested  that the SEC permit it to
modify its reporting  obligations  under Section 13(a) of the Exchange Act until
completion  of the  Chapter  11  bankruptcy  proceeding  by filing  its  monthly
bankruptcy  reports  under  cover  of  Current  Reports  on Form  8-K in lieu of
quarterly reports on Form 10-QSB and annual reports on Form 10-KSB.  The Network

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Connection  has begun filing in this modified  fashion,  although it has not yet
received a response  from the SEC.  The  Network  Connection  does not intend to
appeal the staff's  determination.  When The Network  Connection common stock is
delisted,  public  trading,  if  any,  would  thereafter  be  conducted  in  the
over-the-counter  market  in the  so-called  "pink  sheets,"  or on  the  NASD's
"Electronic  Bulletin Board." Public trading of The Network  Connection's common
stock is  currently  halted on Nasdaq and trading is unlikely to resume prior to
delisting. As a result, it currently is, and when delisted would continue to be,
difficult  to dispose of, or even to obtain  quotations  as to the price of, The
Network  Connection  common stock and the price, if any,  offered for its common
stock may be substantially reduced.

     If the Network  Connection's  common stock is delisted  from trading on the
Nasdaq  SmallCap  Market,  and the market price of its common stock is less than
$5.00 per  share,  subject to certain  exceptions,  trading in its common  stock
would be  subject  to the  requirements  of Rule  15g-9  promulgated  under  the
Exchange Act. Under this rule,  broker/dealers  who recommend such securities to
persons other than  established  customers and accredited  investors  (generally
institutions  or  high-net  worth  individuals)  must  make  a  special  written
suitability  determination for the purchaser and receive the purchaser's written
agreement to a transaction  prior to sale. The  requirements  of Rule 15g-9,  if
applicable, may affect the ability of broker/dealers to sell its securities.

     The Penny Stock Rule also requires additional disclosure in connection with
any trades  involving  a stock  defined as penny  stock (any  non-Nasdaq  equity
security that has a market price or exercise price of less than $5.00 per share,
subject to certain  exceptions).  Unless exempt, the rules require the delivery,
prior to any  transaction  involving a penny  stock,  of a  disclosure  schedule
prepared by the SEC  explaining  important  concepts  involving  the penny stock
market,   the  nature  of  such  market,   terms  used  in  such   market,   the
broker/dealer's  duties  to the  customer,  a  toll-free  telephone  number  for
inquiries  about the  broker/dealer's  disciplinary  history and the  customer's
rights and remedies in case of fraud or abuse in the sale.  Disclosure must also
be made about  commissions  payable to both the broker/dealer and the registered
representative,  and current  quotations for the  securities.  Finally,  monthly
statements must be sent disclosing  recent price information for the penny stock
held in the account and information on the limited market in penny stocks.

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THIS THIRD SUPPLEMENT DOES NOT CONSTITUTE A COMPLETE PROSPECTUS AND SHALL NOT BE
CONSIDERED AN OFFER TO SELL OR A  SOLICITATION  OF AN OFFER TO BUY THE SHARES OF
OUR CLASS A COMMON STOCK TO WHICH IT RELATES.  REFERENCE IS MADE TO THE ORIGINAL
PROSPECTUS,  AS SUPPLEMENTED BY THE FIRST SUPPLEMENT,  THE SECOND SUPPLEMENT AND
THIS THIRD SUPPLEMENT,  FOR INFORMATION WITH RESPECT TO GLOBAL AND THE SHARES OF
CLASS A COMMON STOCK OFFERED THEREBY.

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