EXHIBIT 2.3

STOCK EXCHANGE JOINDER AGREEMENT

STOCK EXCHANGE JOINDER AGREEMENT ("Joinder") dated as of February 21,
2001, by and among Global Information Group USA, Inc., ("GIG"); the new
shareholders of GIG identified on the signature pages hereto (each individually,
a "New Shareholder" and collectively, the "New Shareholders"); the pre-existing
shareholders of GIG (the "Sellers"); ADVA International Inc., a Delaware
corporation ("ADVA"); and Biotel, Inc. ("Biotel").

RECITALS

WHEREAS, on June 19, 2000, GIG, the Sellers, ADVA and Biotel entered
into an Agreement of Stock Exchange whereby the Sellers agreed to convey all
their stock in GIG in exchange for 94.57% of the outstanding capital stock of
ADVA;

WHEREAS, certain of the Sellers, since execution of the Agreement of
Stock Exchange, have sold shares of GIG to certain persons who were not
shareholders of GIG as of June 19, 2000 (the "New Shareholders");

WHEREAS, the New Shareholders desire to join and be bound by all the
terms and conditions of the Agreement of Stock Exchange and all documents
ancillary to the transactions contemplated in the Agreement of Stock Exchange
(the "Ancillary Documents");

WHEREAS, pursuant to Section 9.4 of the Agreement of Stock Exchange,
all the parties thereto must provide their consent prior to amending the
Agreement of Stock Exchange;

NOW THEREFORE, in consideration of the premises and the mutual
representations hereinafter set forth and intending to be legally bound hereby,
the parties hereto agree as follows:

1. The New Shareholders shall, for all purposes of the Agreement of Stock
Exchange, the Ancillary Documents and all the transactions contemplated therein,
be deemed "Sellers", as such term is defined in the Agreement of Stock Exchange.

2. ADVA and Biotel consent to the transfers of the shares to the New
Shareholders and agree to such New Shareholders being deemed "Sellers" for
purposes of the Agreement of Stock Exchange, the Ancillary Documents and all the
transactions contemplated therein.

3. This Joinder may be executed in several counterparts, each of which shall
constitute an original and all of which, when taken together, shall constitute
one agreement.

IN WITNESS WHEREOF, all the parties to this Joinder have caused this Joinder to
be executed and delivered as of the date first set forth above.

SELLERS:

/s/Anthony E. Mohr /s/ H. Smit, power-of-attorney for Charles Langereis
- -------------------------------------------- --------------------------------------------------------------------------
ANTHONY E. MOHR CHARLES LANGEREIS, by Hendrik Smit as power-of-attorney.

/s/Anthony E. Mohr, power-of-attorney for FOG
Investments Limited /s/ H. Smit, power-of-attorney for H.B.G. Sijthoff
- ------------------------------------------------ ---------------------------------------------------
FOG INVESTMENTS LIMITED HENRI B.G. SIJTHOFF, by Hendrik Smit as
By: Anthony E. Mohr as power-of-attorney. power-of-attorney.

/s/ P. L. van Wijngaarden, power-of-attorney
for Hugo Heerema /s/ H. Smit, power-of-attorney for Jouke V.J.P. Brada
- --------------------------------------------------- ----------------------------------------------------
HUGO HEEREMA, by Philip L. van JOUKE V.J.P. BRADA, by Hendrik Smit as power-of-attorney.
Wijngaarden as power-of- attorney.

/s/Philip L. van Wijngaarden, power-of-attorney
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for Femia E. van Wulfften Palthe /s/ Philip L. van Wijngaarden, power-of-attorney for Leonard Van Hulst
- ------------------------------------ --------------------------------------------------------------------------
FEMIA E. VAN WULFFTEN PALTHE, by Philip LEONARD VAN HULST, by Philip L. van Wijngaarden as power-of-attorney.
L. van Wijngaarden as power-of- attorney.

/s/Philip L. van Wijngaarden, power-of-attorney for /s/Philip L. van Wijngaarden, power-of-attorney
- --------------------------------------------------- ---------------------------------------------------------------
Nicole E.A.M. Aarts for Fiona N. Van Hulst
- --------------------------------------------
NICOLE E.A.M. AARTS, by Philip L. van Wijngaarden FIONA N. VAN HULST, by Philip L. van Wijngaarden as power-of- attorney.
- ------------------------------------------------- -----------------------------------------------------------------------
as power-of-attorney.

JOLEC TRADING LIMITED VIEWMONT HOLDINGS LIMITED

By: Intertrust (Curacao) N.V. By: Intertrust (Curacao) N.V.

/s/Gregory Elias /s/Gregory Elias
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Gregory Elias, Managing Director Gregory Elias, Managing Director

SORENSEN' S SECURITIES LIMITED GORILLA VENTURES N.V.

By: Intertrust (Curacao) N.V. By: Intertrust (Curacao) N.V.

MOANA LAKE FINANCE CORP. LINARES CAPITAL LIMITED

By: Intertrust (Curacao) N.V. By: Intertrust (Curacao) N.V.

HACKEN INVESTMENTS LIMITED H EYDAEL B.V.

By: Benno P. Hafner as power-of-attorney. By: Hendrik Smit, Managing Director

/s/Benno P. Hafner /s/ Hendrik Smit
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ADVA INTERNATIONAL, INC. GLOBAL INFORMATION GROUP USA, INC.

By: /s/ George L. Down By: /s/Anthony E. Mohr
---------------------------------------- ----------------------------------------------
Name: George L. Down Name: Anthony E. Mohr
Title: President Title: President

BIOTEL, INC.

By: /s/ Ronald G. Moyer
----------------------------------------
Name: Ronald G. Moyer
Title: President

NEW SHAREHOLDERS:

/s/ Ruud A.M. Pruijm /s/ Jan P.D. Geertman
- -------------------------------------------- --------------------------------------------------
Ruud A.M. Pruijm Jan P.D. Geertman

/s/ Ernst R. Verdonck /s/ Jergen Maijers
- -------------------------------------------- --------------------------------------------------
Ernst R. Verdonck Jergen Maijers

/s/ J. Leffelaar /s/ M. Lavino
- -------------------------------------------- --------------------------------------------------
J. Leffelaar M. Lavino

/s/ Christiaan Ouwingar /s/ Christopher Schuijt
- -------------------------------------------- --------------------------------------------------
Christiaan Ouwinga Christopher Schuijt

Thames Asset Management Ltd.
----------------------------

/s/S.I.J. Zeilstra By: /s/Michael Hoving
- -------------------------------------------- --------------------------------------------------
S.I.J. Zeilstra Name: Michael Hoving
Title: Director