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                                                                    Exhibit 10.5

                         REGISTRATION RIGHTS AGREEMENT


     REGISTRATION RIGHTS AGREEMENT (this "Agreement"), dated as of October 11,
2000, by and among American Telesource International, Inc., a Delaware
corporation, with its headquarters located at 12500 Network Blvd., Suite 407,
San Antonio, Texas 78249 (the "Company"), and each of the undersigned (together
with their respective affiliates and any assignee or transferee of all of their
respective rights hereunder, the "Initial Investors").

     WHEREAS:

     A.   In connection with the Securities Purchase Agreement by and among the
parties hereto of even date herewith (the "Securities Purchase Agreement"), the
Company has agreed, upon the terms and subject to the conditions contained
therein, to issue and sell to the Initial Investors (i) shares of its 6% Series
E Cumulative Convertible Preferred Stock (the "Preferred Stock") that are
convertible into shares of the Company's common stock, par value $.001 per share
(the "Common Stock"), upon the terms and subject to the limitations and
conditions set forth in the Certificate of Designations, Rights, Preferences,
Privileges and Restrictions with respect to the Preferred Stock, as corrected by
the Certificate of Correction filed with the State of Delaware on October 11,
2000 and the Certificate of Correction filed with the State of Delaware on
October 12, 2000 (the "Certificate of Designation"); and (ii) warrants (the
"Warrants") to acquire Three Million Six Hundred Thirty-Six Thousand Three
Hundred Sixty-Four (3,636,364) shares of Common Stock, upon the terms and
conditions and subject to the limitations and conditions set forth in the
Warrants dated October 11, 2000; and

     B.   To induce the Initial Investors to execute and deliver the Securities
Purchase Agreement, the Company has agreed to provide certain registration
rights under the Securities Act of 1933, as amended, and the rules and
regulations thereunder, or any similar successor statute (collectively, the
"1933 Act"), and applicable state securities laws;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and each of the
Initial Investors hereby agree as follows:

1.   DEFINITIONS.

a.        As used in this Agreement, the following terms shall have the
following meanings:

b.
     (i)  "Investors" means the Initial Investors and any transferee or assignee
     who agrees to become bound by the provisions of this Agreement in
     accordance with Section 9 hereof.
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     (i)  "register," "registered," and "registration" refer to a registration
     effected by preparing and filing a Registration Statement or Statements in
     compliance with the 1933 Act and pursuant to Rule 415 under the 1933 Act or
     any successor rule providing for offering securities on a continuous basis
     ("Rule 415"), and the declaration or ordering of effectiveness of such
     Registration Statement by the United States Securities and Exchange
     Commission (the "SEC").

     (i)  "Registrable Securities" means (A) the Conversion Shares issued or
     issuable upon conversion of or otherwise pursuant to the Preferred Shares
     (including, without limitation, the Preferred Shares issuable at the Second
     Closing (as defined in the Securities Purchase Agreement), any shares
     issued or issuable upon exercise of the Investment Options (as defined in
     the Certificate of Designation or pursuant to Articles V, VI.D(ii) and VI.F
     of the Certificate of Designation and Section 2(c) herein); (B) the Warrant
     Shares issued or issuable and any shares of capital stock issued or
     issuable upon exercise of the Warrants (including the Warrants issuable at
     the Second Closing); and (C) any shares of capital stock issued or issuable
     as a dividend on or in exchange for or otherwise with respect to any of the
     foregoing.

     (i)  "Registration Statement(s)" means a registration statement(s) of the
     Company under the 1933 Act.

b.        Capitalized terms used herein and not otherwise defined herein shall
have the respective meanings set forth in the Securities Purchase Agreement.

2.   REGISTRATION.
     ------------

a.        Mandatory Registration. The Company shall prepare, and, on or prior to
          ----------------------
the earlier of (i) the date (the "Filing Date") which is thirty (30) days after
the date of the First Closing under the Securities Purchase Agreement (the
"Closing Date"), (ii) the date on which a registration statement registering for
sale the Common Stock pursuant to the Equity Line (as defined in the Securities
Purchase Agreement), file with the SEC a Registration Statement on Form S-3 (or,
if Form S-3 is not then available, on such form of Registration Statement as is
then available to effect a registration of the Registrable Securities, subject
to the consent of the Initial Investors, which consent will not be unreasonably
withheld) covering the resale of the Registrable Securities, which Registration
Statement, to the extent allowable under the 1933 Act and the rules and
regulations promulgated thereunder (including Rule 416), shall state that such
Registration Statement also covers such indeterminate number of additional
shares of Common Stock as may become issuable upon conversion of or otherwise
pursuant to the Preferred Shares (including, but not limited to, shares issued
or issuable upon exercise of the Investment Options) and exercise of or
otherwise pursuant to the Warrants to prevent dilution resulting from stock
splits, stock dividends or similar transactions.  The number of shares of Common
Stock initially included in such Registration Statement shall be no less than
two (2) times the aggregate number of Conversion Shares and Warrant Shares that
are then issuable upon conversion of or otherwise pursuant to the Preferred
Shares (including upon exercise of the Investment Options under the Certificate
of Designation) (based on the lesser of the Market Price and the Fixed
Conversion Price (each as defined in the Certificate of Designation) then be in
effect) and the exercise of or otherwise pursuant to the Warrants, in each case
without regard to any limitation on the

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Investor's ability to convert the Preferred Shares or exercise the Warrants. The
Company acknowledges that the number of shares initially included in the
Registration Statement represents a good faith estimate of the maximum number of
shares issuable upon conversion of or otherwise pursuant to the Preferred Shares
(including upon exercise of the Investment Options under the Certificate of
Designation) and exercise of or otherwise pursuant to the Warrants. The
Registration Statement (and each amendment or supplement thereto, and each
request for acceleration of effectiveness thereof) shall be provided to and
subject to the approval of) the Initial Investors and their counsel prior to its
filing or other submission; provided, however, that such approval of the Initial
Investors and their counsel shall not be unreasonably withheld.

b.        Underwritten Offering.  If any offering pursuant to a Registration
          ---------------------
Statement pursuant to Section 2(a) hereof involves an underwritten offering, the
Investors who hold a majority in interest of the Registrable Securities subject
to such underwritten offering, with the consent of a majority-in-interest of the
Initial Investors, shall have the right to select one legal counsel and an
investment banker or bankers and manager or managers to administer the offering,
which investment banker or bankers or manager or managers shall be reasonably
satisfactory to the Company.  In the event that any Investors elect not to
participate in such underwritten offering, the Registration Statement covering
all of the Registrable Securities shall contain appropriate plans of
distribution reasonably satisfactory to the Investors participating in such
underwritten offering and the Investors electing not to participate in such
underwritten offering (including, without limitation, the ability of non-
participating Investors to sell from time to time at any time during the
effectiveness of such Registration Statement).

c.        Payments by the Company.  The Company shall use its best efforts to
          -----------------------
obtain effectiveness of the Registration Statement as soon as practicable, but
in any event not later than the one hundred twentieth (120th) day after the
Closing Date (the "Registration Deadline").  If (i) the Registration
Statement(s) covering the Registrable Securities required to be filed by the
Company pursuant to Section 2(a) hereof is not declared effective by the SEC by
the Registration Deadline, or (ii) after the Registration Statement has been
declared effective by the SEC, sales of all of the Registrable Securities cannot
be made pursuant to the Registration Statement, or (iii) the Common Stock is not
listed or included for quotation on the Nasdaq National Market ("Nasdaq"), the
Nasdaq SmallCap Market ("Nasdaq SmallCap"), the New York Stock Exchange (the
"NYSE") or the American Stock Exchange (the "AMEX") after being so listed or
included for quotation, then the Company will make payments to the Investors in
such amounts and at such times as shall be determined pursuant to this Section
2(c) as partial relief for the damages to the Investors by reason of any such
delay in or reduction of their ability to sell the Registrable Securities (which
remedy shall not be exclusive of any other remedies available at law or in
equity).  The Company shall pay to each holder of the Preferred Shares or
Registrable Securities an amount equal to the stated value of the Preferred
Shares then outstanding (and, in the case of holders of Registrable Securities,
the stated value of Preferred Shares from which such Registrable Securities were
converted or the exercise price of the Investment Options and Warrants upon
exercise of which such Registrable Securities were received, as applicable)
("Aggregate Share Price") multiplied by three hundreths (.03) times the sum of:
(i) the number of months (prorated for partial months) after the Registration
Deadline and prior to the date the Registration Statement is declared effective
by the SEC; provided, however, that there shall be excluded from such period any
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delays which are solely attributable to changes required by the

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Investors in the Registration Statement with respect to information relating to
the Investors, including, without limitation, changes to the plan of
distribution, or to the failure of the Investors to conduct their review of the
Registration Statement pursuant to Section 3(h) below in a reasonably prompt
manner; (ii) the number of months (prorated for partial months) during the
Registration Period (as defined below) that sales of all of the Registrable
Securities cannot be made pursuant to the Registration Statement after the
Registration Statement has been declared effective (including, without
limitation, when sales cannot be made by reason of the Company's failure to
properly supplement or amend the prospectus included therein in accordance with
the terms of this Agreement (including Section 3(b) hereof or otherwise), but
excluding any days during an Allowed Delay (as defined in Section 3(f)); and
(iii) the number of months (prorated for partial months) that the Common Stock
is not listed or included for quotation on the Nasdaq, Nasdaq SmallCap, NYSE or
AMEX or that trading thereon is halted after the Registration Statement has been
declared effective. (For example, if the Registration Statement becomes
effective one (1) month after the end the Registration Deadline, the Company
would pay $30,000 for each $1,000,000 of Aggregate Share Price. If thereafter,
sales could not be made pursuant to the Registration Statement for an additional
period of one (1) month, the Company would pay an additional $30,000 for each
$1,000,000 of Aggregate Share Price.) Such amounts shall be paid in cash or, at
each Investor's option, may be added to the Conversion Amount (as defined in the
Certificate of Designation) of the Preferred Shares pursuant to Article VI.A(a)
of the Certificate of Designation and thereafter be convertible into Common
Stock at the "Conversion Price" (as defined in the Certificate of Designation)
in accordance with the terms of the Preferred Shares. Any shares of Common Stock
issued upon conversion of such amounts shall be Registrable Securities. If the
Investor desires to convert the amounts due hereunder into Registrable
Securities, it shall so notify the Company in writing within two (2) business
days of the date on which such amounts are first payable in cash and such
amounts shall be so convertible (pursuant to the mechanics set forth in the
Certificate of Designation), beginning on the last day upon which the cash
amount would otherwise be due in accordance with the following sentence.
Payments of cash pursuant hereto shall be made within five (5) days after the
end of each period that gives rise to such obligation, provided that, if any
such period extends for more than thirty (30) days, interim payments shall be
made for each such thirty (30) day period.

d.        Piggy-Back Registrations. Subject to the last sentence of this Section
          ------------------------
2(d), if at any time prior to the expiration of the Registration Period (as
hereinafter defined) the Company shall determine to file with the SEC a
Registration Statement relating to an offering for its own account or the
account of others under the 1933 Act of any of its equity securities (other than
on Form S-4 or Form S-8 or their then equivalents relating to equity securities
to be issued solely in connection with any acquisition of any entity or business
or equity securities issuable in connection with stock option or other employee
benefit plans), the Company shall send to each Investor who is entitled to
registration rights under this Section 2(d) written notice of such determination
and, if within fifteen (15) days after the effective date of such notice, such
Investor shall so request in writing, the Company shall include in such
Registration Statement all or any part of the Registrable Securities such
Investor requests to be registered, except that if, in connection with any
underwritten public offering for the account of the Company the managing
underwriter(s) thereof shall impose a limitation on the number of shares of
Common Stock which may be included in the Registration Statement because, in
such underwriter(s)' judgment,

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marketing or other factors dictate such limitation is necessary to facilitate
public distribution, then the Company shall be obligated to include in such
Registration Statement only such limited portion of the Registrable Securities
with respect to which such Investor has requested inclusion hereunder as the
underwriter shall permit. Any exclusion of Registrable Securities shall be made
pro rata among the Investors seeking to include Registrable Securities in
proportion to the number of Registrable Securities sought to be included by such
Investors; provided, however, that the Company shall not exclude any Registrable
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Securities unless the Company has first excluded all outstanding securities, the
holders of which are not entitled by contract to inclusion of such securities in
such Registration Statement or are not entitled to pro rata inclusion with the
Registrable Securities; and provided, further, however, that, after giving
                            --------  -------  -------
effect to the immediately preceding proviso, any exclusion of Registrable
Securities shall be made pro rata with holders of other securities having the
contractual right to include such securities in the Registration Statement other
than holders of securities entitled to inclusion of their securities in such
Registration Statement by reason of demand registration rights. No right to
registration of Registrable Securities under this Section 2(d) shall be
construed to limit any registration required under Section 2(a) hereof. If an
offering in connection with which an Investor is entitled to registration under
this Section 2(d) is an underwritten offering, then each Investor whose
Registrable Securities are included in such Registration Statement shall, unless
otherwise agreed by the Company, offer and sell such Registrable Securities in
an underwritten offering using the same underwriter or underwriters and, subject
to the provisions of this Agreement, on the same terms and conditions as other
shares of Common Stock included in such underwritten offering. Notwithstanding
anything to the contrary set forth herein, the registration rights of the
Investors pursuant to this Section 2(d) shall only be available in the event the
Company fails to timely file, obtain effectiveness or maintain effectiveness of
any Registration Statement to be filed pursuant to Section 2(a) in accordance
with the terms of this Agreement.

e.        Eligibility for Form S-3.  The Company represents and warrants that it
          ------------------------
meets the registrant eligibility and transaction requirements for the use of
Form S-3 for registration of the sale by the Initial Investors and any other
Investors of the Registrable Securities and the Company shall file all reports
required to be filed by the Company with the SEC in a timely manner so as to
maintain such eligibility for the use of Form S-3.

3.   OBLIGATIONS OF THE COMPANY.
     --------------------------
a.        In connection with the registration of the Registrable Securities, the
Company shall have the following obligations:

b.        The Company shall prepare promptly, and file with the SEC as soon as
practicable after the Closing Date (but in no event later than the Filing Date),
a Registration Statement with respect to the number of Registrable Securities
provided in Section 2(a), and thereafter use its best efforts to cause such
Registration Statement relating to Registrable Securities to become effective as
soon as possible after such filing, (but in no event later than the Registration
Deadline), and keep the Registration Statement effective pursuant to Rule 415 at
all times until such date as is the earlier of (i) the date on which all of the
Registrable Securities have been sold and (ii) the date on which the Registrable
Securities (in the opinion of counsel to the Initial Investors) may be
immediately sold to the public without registration or restriction (including
without limitation as to volume by each holder thereof) under the 1933 Act (the
"Registration Period"), which Registration Statement (including any amendments
or

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supplements thereto and prospectuses contained therein) shall not contain any
untrue statement of a material fact or omit to state a material fact required to
be stated therein, or necessary to make the statements therein not misleading.

c.        The Company shall prepare and file with the SEC such amendments
(including post-effective amendments) and supplements to the Registration
Statements and the prospectus used in connection with the Registration
Statements as may be necessary to keep the Registration Statements effective at
all times during the Registration Period, and, during such period, comply with
the provisions of the 1933 Act with respect to the disposition of all
Registrable Securities of the Company covered by the Registration Statements
until such time as all of such Registrable Securities have been disposed of in
accordance with the intended methods of disposition by the seller or sellers
thereof as set forth in the Registration Statements.  In the event that on any
Trading Day (as defined in the Certificate of Designation) (the "Registration
Trigger Date") the number of shares available under a Registration Statement
filed pursuant to this Agreement is insufficient to cover all of the Registrable
Securities issued or issuable upon conversion of or otherwise pursuant to the
Preferred Shares (including upon exercise of the Investment Options under the
Certificate of Designation) (based on the lesser of the Market Price and the
Fixed Conversion Price (each as defined in the Certificate of Designation) then
in effect) and exercise of or otherwise pursuant to the Warrants, in each case
without giving effect to any limitations on the Investors' ability to convert
the Preferred Shares or exercise the Warrants, the Company shall amend the
Registration Statement, or file a new Registration Statement (on the short form
available therefore, if applicable), or both, so as to cover two hundred percent
(200%) of  all of the Registrable Securities so issued or issuable (without
giving effect to any limitations on conversion or exercise contained in the
Certificate of Designation or Warrants, as applicable) as of the Registration
Trigger Date, in each case, as soon as practicable, but in any event within
twenty (20) business days after the necessity therefor arises (based on the
market price of the Common Stock and other relevant factors on which the Company
reasonably elects to rely).  The Company shall use its best efforts to cause
such amendment and/or new Registration Statement to become effective as soon as
practicable following the filing thereof, but in any event within sixty (60)
days of the Registration Trigger Date.  The provisions of Section 2(c) above
shall be applicable with respect to the Company's obligations under this Section
3(b).

d.        The Company shall furnish to each Investor whose Registrable
Securities are included in a Registration Statement and its legal counsel (i)
promptly after the same is prepared and publicly distributed, filed with the
SEC, or received by the Company, one copy of each Registration Statement and any
amendment thereto, each preliminary prospectus and prospectus and each amendment
or supplement thereto, and, in the case of the Registration Statement referred
to in Section 2(a), each letter written by or on behalf of the Company to the
SEC or the staff of the SEC, and each item of correspondence from the SEC or the
staff of the SEC, in each case relating to such Registration Statement (other
than any portion of any thereof which contains information for which the Company
has sought confidential treatment), and (ii) such number of copies of a
prospectus, including a preliminary prospectus, and all amendments and
supplements thereto and such other documents as such Investor may reasonably
request in order to facilitate the disposition of the Registrable Securities
owned by such Investor. The Company will immediately notify each Investor by
facsimile of the effectiveness of each Registration Statement or any post-
effective amendment. The Company will promptly respond to any and all

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comments received from the SEC, with a view towards causing each Registration
Statement or any amendment thereto to be declared effective by the SEC as soon
as practicable and shall file an acceleration request as soon as practicable
following the resolution or clearance of all SEC comments or, if applicable,
following notification by the SEC that any such Registration Statement or any
amendment thereto will not be subject to review.

e.        The Company shall use reasonable efforts to (i) register and qualify
the Registrable Securities covered by the Registration Statements under such
other securities or "blue sky" laws of such jurisdictions in the United States
as the Investors who hold a majority in interest of the Registrable Securities
being offered reasonably request, (ii) prepare and file in those jurisdictions
such amendments (including post-effective amendments) and supplements to such
registrations and qualifications as may be necessary to maintain the
effectiveness thereof during the Registration Period, (iii) take such other
actions as may be necessary to maintain such registrations and qualifications in
effect at all times during the Registration Period, and (iv) take all other
actions reasonably necessary or advisable to qualify the Registrable Securities
for sale in such jurisdictions; provided, however, that the Company shall not be
                                --------  -------
required in connection therewith or as a condition thereto to (a) qualify to do
business in any jurisdiction where it would not otherwise be required to qualify
but for this Section 3(d), (b) subject itself to general taxation in any such
jurisdiction, (c) file a general consent to service of process in any such
jurisdiction, (d) provide any undertakings that cause the Company undue expense
or burden, or (e) make any change in its charter or bylaws, which in each case
the Board of Directors of the Company determines to be contrary to the best
interests of the Company and its stockholders.

f.        In the event Investors who hold a majority-in-interest of the
Registrable Securities being offered in the offering  (with the approval of a
majority-in-interest of the Initial Investors) select underwriters for the
offering, the Company shall enter into and perform its obligations under an
underwriting agreement, in usual and customary form, including, without
limitation, customary indemnification and contribution obligations, with the
underwriters of such offering.

g.        As promptly as practicable after becoming aware of such event, the
Company shall notify each Investor of the happening of any event, of which the
Company has knowledge, as a result of which the prospectus included in any
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omission to state a material fact required to be stated therein
or necessary to make the statements therein not misleading, and use its best
efforts promptly to prepare a supplement or amendment to any Registration
Statement to correct such untrue statement or omission, and deliver such number
of copies of such supplement or amendment to each Investor as such Investor may
reasonably request; provided that, for not more than five (5) consecutive
trading days (or a total of not more than twenty (20) trading days in any twelve
(12) month period), the Company may delay the disclosure of material non-public
information concerning the Company (as well as prospectus or Registration
Statement updating) the disclosure of which at the time is not, in the good
faith opinion of the Company, in the best interests of the Company (an "Allowed
Delay"); provided, further, that the Company shall promptly (i) notify the
Investors in writing of the existence of (but in no event, without the prior
written consent of an Investor, shall the Company disclose to such Investor any
of the facts or circumstances regarding) material non-public information giving
rise to an Allowed Delay and (ii) advise the Investors in writing to cease all
sales under such Registration Statement until the

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end of the Allowed Delay. Upon expiration of the Allowed Delay, the Company
shall again be bound by the first sentence of this Section 3(f) with respect to
the information giving rise thereto.

h.        The Company shall use its best efforts to prevent the issuance of any
stop order or other suspension of effectiveness of any Registration Statement,
and, if such an order is issued, to obtain the withdrawal of such order at the
earliest possible moment and to notify each Investor who holds Registrable
Securities being sold (or, in the event of an underwritten offering, the
managing underwriters) of the issuance of such order and the resolution thereof.

i.        The Company shall permit a single firm of counsel designated by the
Initial Investors to review such Registration Statement, and all amendments and
supplements thereto (as well as all requests for acceleration or effectiveness
thereof and any correspondence between the Company and the SEC relating to the
Registration Statement) a reasonable period of time prior to their filing with
the SEC, and not file any document (nor send any correspondence) in a form to
which such counsel reasonably objects and will not request acceleration of such
Registration Statement without prior notice to such counsel.  The sections of
such Registration Statement covering information with respect to the Investors,
the Investor's beneficial ownership of securities of the Company or the
Investors intended method of disposition of Registrable Securities shall conform
to the information provided to the Company by each of the Investors.

j.        The Company shall make generally available to its security holders as
soon as practicable, but not later than ninety (90) days after the close of the
period covered thereby, an earnings statement (in form complying with the
provisions of Rule 158 under the 1933 Act) covering a twelve-month period
beginning not later than the first day of the Company's fiscal quarter next
following the effective date of the Registration Statement.

k.        At the request of any Investor, the Company shall furnish, on the date
that Registrable Securities are delivered to an underwriter, if any, for sale in
connection with any Registration Statement or, if such securities are not being
sold by an underwriter, on the date of effectiveness thereof (i) an opinion,
dated as of such date, from counsel representing the Company for purposes of
such Registration Statement, in form, scope and substance as is customarily
given in an underwritten public offering, addressed to the underwriters, if any,
and the Investors and (ii) a letter, dated such date, from the Company's
independent certified public accountants in form and substance as is customarily
given by independent certified public accountants to underwriters in an
underwritten public offering, addressed to the underwriters, if any, and the
Investors.

l.        The Company shall make available for inspection by (i) any Investor,
(ii) any underwriter participating in any disposition pursuant to a Registration
Statement, (iii) one firm of attorneys and one firm of accountants or other
agents retained by the Initial Investors, (iv) one firm of attorneys and one
firm of accountants or other agents retained by all other Investors, and (v) one
firm of attorneys retained by all such underwriters (collectively, the
"Inspectors") all pertinent financial and other records, and pertinent corporate
documents and properties of the Company (collectively, the "Records"), as shall
be reasonably deemed necessary by each Inspector to enable each Inspector to
exercise its due diligence responsibility, and cause the Company's officers,
directors and employees to supply all information which any Inspector may
reasonably request for purposes of such due diligence; provided, however, that
                                                       --------  -------
each Inspector shall hold in confidence and shall not make any disclosure
(except to an Investor) of any Record or other information which the Company
determines in good faith to be confidential, and of

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which determination the Inspectors are so notified, unless (a) the disclosure of
such Records is necessary to avoid or correct a misstatement or omission in any
Registration Statement, (b) the release of such Records is ordered pursuant to a
subpoena or other order from a court or government body of competent
jurisdiction, or (c) the information in such Records has been made generally
available to the public other than by disclosure in violation of this or any
other agreement. The Company shall not be required to disclose any confidential
information in such Records to any Inspector until and unless such Inspector
shall have entered into confidentiality agreements (in form and substance
satisfactory to the Company) with the Company with respect thereto,
substantially in the form of this Section 3(k). Each Investor agrees that it
shall, upon learning that disclosure of such Records is sought in or by a court
or governmental body of competent jurisdiction or through other means, give
prompt notice to the Company and allow the Company, at its expense, to undertake
appropriate action to prevent disclosure of, or to obtain a protective order
for, the Records deemed confidential. Nothing herein (or in any other
confidentiality agreement between the Company and any Investor) shall be deemed
to limit the Investor's ability to sell Registrable Securities in a manner which
is otherwise consistent with applicable laws and regulations.

m.        The Company shall hold in confidence and not make any disclosure of
information concerning an Investor provided to the Company unless (i) disclosure
of such information is necessary to comply with federal or state securities
laws, (ii) the disclosure of such information is necessary to avoid or correct a
misstatement or omission in any Registration Statement, (iii) the release of
such information is ordered pursuant to a subpoena or other order from a court
or governmental body of competent jurisdiction, or (iv) such information has
been made generally available to the public other than by disclosure in
violation of this or any other agreement.  The Company agrees that it shall,
upon learning that disclosure of such information concerning an Investor is
sought in or by a court or governmental body of competent jurisdiction or
through other means, give prompt notice to such Investor prior to making such
disclosure, and allow the Investor, at its expense, to undertake appropriate
action to prevent disclosure of, or to obtain a protective order for, such
information.

n.        The Company shall (i) cause all the Registrable Securities covered by
the Registration Statement to be listed on each national securities exchange on
which securities of the same class or series issued by the Company are then
listed, if any, if the listing of such Registrable Securities is then permitted
under the rules of such exchange, or (ii) to the extent the securities of the
same class or series are not then listed on a national securities exchange,
secure the designation and quotation of all the Registrable Securities covered
by the Registration Statement on Nasdaq or, if not eligible for Nasdaq on the
Nasdaq SmallCap and, without limiting the generality of the foregoing, to
arrange for at least two market makers to register with the National Association
of Securities Dealers, Inc. ("NASD") as such with respect to such Registrable
Securities.

o.        The Company shall provide a transfer agent and registrar, which may be
a single entity, for the Registrable Securities not later than the effective
date of the Registration Statement.

p.        The Company shall cooperate with the Investors who hold Registrable
Securities being offered and the managing underwriter or underwriters, if any,
to facilitate the timely preparation and delivery of certificates (not bearing
any restrictive legends) representing

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Registrable Securities to be offered pursuant to such Registration Statement and
enable such certificates to be in such denominations or amounts, as the case may
be, as the managing underwriter or underwriters, if any, or the Investors may
reasonably request and registered in such names as the managing underwriter or
underwriters, if any, or the Investors may request, and, within three (3)
business days after a Registration Statement which includes Registrable
Securities is ordered effective by the SEC, the Company shall deliver, and shall
cause legal counsel selected by the Company to deliver, to the transfer agent
for the Registrable Securities (with copies to the Investors whose Registrable
Securities are included in such Registration Statement) an instruction in the
form attached hereto as Exhibit 1 and an opinion of such counsel in the form
attached hereto as Exhibit 2.

q.        At the request of the holders of a majority-in-interest of the
Registrable Securities, the Company shall prepare and file with the SEC such
amendments (including post-effective amendments) and supplements to a
Registration Statement and any prospectus used in connection with the
Registration Statement as may be necessary in order to change the plan of
distribution set forth in such Registration Statement.

r.        The Company shall not, and shall not agree to, allow the holders of
any securities of the Company to include any of their securities in any
Registration Statement under Section 2(a) hereof or any amendment or supplement
thereto under Section 3(b) hereof without the consent of the holders of a
majority-in-interest of the Registrable Securities; provided, however, that the
Company may include on the Registration Statement up to 175,000 shares of Common
Stock issuable upon exercise of those warrants previously issued and outstanding
on the date of this Agreement in connection with the Equity Line (as defined in
the Securities Purchase Agreement). In addition, the Company shall not offer any
securities for its own account or the account of others in any Registration
Statement under Section 2(a) hereof or any amendment or supplement thereto under
Section 3(b) hereof without the consent of the holders of a majority-in-
interest of the Registrable Securities.

s.        The Company shall take all other reasonable actions necessary to
expedite and facilitate disposition by the Investors of Registrable Securities
pursuant to a Registration Statement.

t.        The Company shall comply with all applicable laws related to a
Registration Statement and offering and sale of securities and all applicable
rules and regulations of governmental authorities in connection therewith
(including without limitation the 1933 Act and the 1934 Act and the rules and
regulations promulgated by the SEC).

4.   OBLIGATIONS OF THE INVESTORS.
     ----------------------------

a.        In connection with the registration of the Registrable Securities, the
Investors shall have the following obligations:

b.        It shall be a condition precedent to the obligations of the Company to
complete the registration pursuant to this Agreement with respect to the
Registrable Securities of a particular Investor that such Investor shall furnish
to the Company such information regarding itself, the Registrable Securities
held by it and the intended method of disposition of the Registrable Securities
held by it as shall be reasonably required to effect the registration of such
Registrable Securities and shall execute such documents in connection with such
registration as the Company may reasonably request.  At least three (3) business
days prior to the first

                                       10
<PAGE>

anticipated filing date of the Registration Statement, the Company shall notify
each Investor of the information the Company requires from each such Investor.

c.        Each Investor, by such Investor's acceptance of the Registrable
Securities, agrees to cooperate with the Company as reasonably requested by the
Company in connection with the preparation and filing of the Registration
Statements hereunder, unless such Investor has notified the Company in writing
of such Investor's election to exclude all of such Investor's Registrable
Securities from the Registration Statements.

d.        In the event Investors holding a majority-in-interest of the
Registrable Securities being registered (with the approval of the Initial
Investors) determine to engage the services of an underwriter, each Investor
agrees to enter into and perform such Investor's obligations under an
underwriting agreement, in usual and customary form, including, without
limitation, customary indemnification and contribution obligations, with the
managing underwriter of such offering and take such other actions as are
reasonably required in order to expedite or facilitate the disposition of the
Registrable Securities, unless such Investor has notified the Company in writing
of such Investor's election to exclude all of such Investor's Registrable
Securities from such Registration Statement.

e.        Each Investor agrees that, upon receipt of any notice from the Company
of the happening of any event of the kind described in Section 3(f) or 3(g),
such Investor will immediately discontinue disposition of Registrable Securities
pursuant to the Registration Statement covering such Registrable Securities
until such Investor's receipt of the copies of the supplemented or amended
prospectus contemplated by Section 3(f) or 3(g) and, if so directed by the
Company, such Investor shall deliver to the Company (at the expense of the
Company) or destroy (and deliver to the Company a certificate of destruction)
all copies in such Investor's possession, of the prospectus covering such
Registrable Securities current at the time of receipt of such notice.

f.        No Investor may participate in any underwritten registration hereunder
unless such Investor (i) agrees to sell such Investor's Registrable Securities
on the basis provided in any underwriting arrangements in usual and customary
form entered into by the Company, (ii) completes and executes all
questionnaires, powers of attorney, indemnities, underwriting agreements and
other documents reasonably required under the terms of such underwriting
arrangements, and (iii) agrees to pay its pro rata share of all underwriting
discounts and commissions and any expenses in excess of those payable by the
Company pursuant to Section 5 below.

5.   EXPENSES OF REGISTRATION.
     ------------------------

a.        All reasonable expenses, other than underwriting discounts and
commissions, incurred in connection with registrations, filings or
qualifications pursuant to Sections 2 and 3, including, without limitation, all
registration, listing and qualification fees, printers and accounting fees, the
fees and disbursements of counsel for the Company, and the reasonable fees and
disbursements of one counsel selected by the Initial Investors pursuant to
Sections 2(b) and 3(h) hereof shall be borne by the Company.

6.   INDEMNIFICATION.
     ---------------

a.        In the event any Registrable Securities are included in a Registration
Statement under this Agreement:

                                       11
<PAGE>

b.        To the extent permitted by law, the Company will indemnify, hold
harmless and defend (i) each Investor who holds such Registrable Securities,
(ii) the directors, officers, partners, employees, agents and each person who
controls any Investor within the meaning of the 1933 Act or the Securities
Exchange Act of 1934, as amended (the "1934 Act"), if any, (iii) any underwriter
(as defined in the 1933 Act) for the Investors, and (iv) the directors,
officers, partners, employees and each person who controls any such underwriter
within the meaning of the 1933 Act or the 1934 Act, if any (each, an
"Indemnified Person"), against any joint or several losses, claims, damages,
liabilities or expenses (collectively, together with actions, proceedings or
inquiries by any regulatory or self-regulatory organization, whether commenced
or threatened, in respect thereof, "Claims") to which any of them may become
subject insofar as such Claims arise out of or are based upon: (i) any untrue
statement or alleged untrue statement of a material fact in a Registration
Statement or the omission or alleged omission to state therein a material fact
required to be stated or necessary to make the statements therein not
misleading; (ii) any untrue statement or alleged untrue statement of a material
fact contained in any preliminary prospectus if used prior to the effective date
of such Registration Statement, or contained in the final prospectus (as amended
or supplemented, if the Company files any amendment thereof or supplement
thereto with the SEC) or the omission or alleged omission to state therein any
material fact necessary to make the statements made therein, in light of the
circumstances under which the statements therein were made, not misleading; or
(iii) any violation or alleged violation by the Company of the 1933 Act, the
1934 Act, any other law, including, without limitation, any state securities
law, or any rule or regulation thereunder relating to the offer or sale of the
Registrable Securities (the matters in the foregoing clauses (i) through (iii)
being, collectively, "Violations").  Subject to the restrictions set forth in
Section 6(c) with respect to the number of legal counsel, the Company shall
reimburse the Indemnified Person, promptly as such expenses are incurred and are
due and payable, for any reasonable legal fees or other reasonable expenses
incurred by them in connection with investigating or defending any such Claim.
Notwithstanding anything to the contrary contained herein, the indemnification
agreement contained in this Section 6(a): (i) shall not apply to a Claim arising
out of or based upon a Violation which occurs in reliance upon and in conformity
with information furnished in writing to the Company by any Indemnified Person
or underwriter for such Indemnified Person expressly for use in connection with
the preparation of such Registration Statement or any such amendment thereof or
supplement thereto; (ii) shall not apply to amounts paid in settlement of any
Claim if such settlement is effected without the prior written consent of the
Company, which consent shall not be unreasonably withheld; and (iii) with
respect to any preliminary prospectus, shall not inure to the benefit of any
Indemnified Person if the untrue statement or omission of material fact
contained in the preliminary prospectus was corrected on a timely basis in the
prospectus, as then amended or supplemented, such corrected prospectus was
timely made available by the Company pursuant to Section 3(c) hereof, and the
Indemnified Person was promptly advised in writing not to use the incorrect
prospectus prior to the use giving rise to a Violation and such Indemnified
Person, notwithstanding such advice, used it.  Such indemnity shall remain in
full force and effect regardless of any investigation made by or on behalf of
the Indemnified Person and shall survive the transfer of the Registrable
Securities by the Investors pursuant to Section 9.

                                       12
<PAGE>

c.        In connection with any Registration Statement in which an Investor is
participating, each such Investor agrees severally and not jointly to indemnify,
hold harmless and defend, to the same extent and in the same manner set forth in
Section 6(a), the Company, each of its directors, each of its officers who signs
the Registration Statement, each person, if any, who controls the Company within
the meaning of the 1933 Act or the 1934 Act, any underwriter and any other
stockholder selling securities pursuant to the Registration Statement or any of
its directors or officers or any person who controls such stockholder or
underwriter within the meaning of the 1933 Act or the 1934 Act (collectively and
together with an Indemnified Person, an "Indemnified Party"), against any Claim
to which any of them may become subject, under the 1933 Act, the 1934 Act or
otherwise, insofar as such Claim arises out of or is based upon any Violation by
such Investor, in each case to the extent (and only to the extent) that such
Violation occurs in reliance upon and in conformity with written information
furnished to the Company by such Investor expressly for use in connection with
such Registration Statement; and subject to Section 6(c) such Investor will
reimburse any legal or other expenses (promptly as such expenses are incurred
and are due and payable) reasonably incurred by them in connection with
investigating or defending any such Claim; provided, however, that the indemnity
                                           --------  -------
agreement contained in this Section 6(b) shall not apply to amounts paid in
settlement of any Claim if such settlement is effected without the prior written
consent of such Investor, which consent shall not be unreasonably withheld;
provided, further, however, that the Investor shall be liable under this
--------  -------  -------
Agreement (including this Section 6(b) and Section 7) for only that amount as
does not exceed the net proceeds to such Investor as a result of the sale of
Registrable Securities pursuant to such Registration Statement.  Such indemnity
shall remain in full force and effect regardless of any investigation made by or
on behalf of such Indemnified Party and shall survive the transfer of the
Registrable Securities by the Investors pursuant to Section 9. Notwithstanding
anything to the contrary contained herein, the indemnification agreement
contained in this Section 6(b) with respect to any preliminary prospectus shall
not inure to the benefit of any Indemnified Party if the untrue statement or
omission of material fact contained in the preliminary prospectus was corrected
on a timely basis in the prospectus, as then amended or supplemented.

d.        Promptly after receipt by an Indemnified Person or Indemnified Party
under this Section 6 of notice of the commencement of any action (including any
governmental action), such Indemnified Person or Indemnified Party shall, if a
Claim in respect thereof is to be made against any indemnifying party under this
Section 6, deliver to the indemnifying party a written notice of the
commencement thereof, and the indemnifying party shall have the right to
participate in, and, to the extent the indemnifying party so desires, jointly
with any other indemnifying party similarly noticed, to assume control of the
defense thereof with counsel mutually satisfactory to the indemnifying party and
the Indemnified Person or the Indemnified Party, as the case may be; provided,
                                                                     --------
however, that an Indemnified Person or Indemnified Party shall have the right to
-------
retain its own counsel with the fees and expenses to be paid by the indemnifying
party, if, in the reasonable opinion of counsel retained by the indemnifying
party, the representation by such counsel of the Indemnified Person or
Indemnified Party and the indemnifying party would be inappropriate due to
actual or potential differing interests between such Indemnified Person or
Indemnified Party and any other party represented by such counsel in such
proceeding.  The indemnifying party shall pay for only one separate legal
counsel for  the Indemnified Persons or the Indemnified Parties, as applicable,
and such legal counsel shall be

                                       13
<PAGE>

selected by Investors holding a majority-in-interest of the Registrable
Securities included in the Registration Statement to which the Claim relates
(with the approval of a majority-in-interest of the Initial Investors), if the
Investors are entitled to indemnification hereunder, or the Company, if the
Company is entitled to indemnification hereunder, as applicable. The failure to
deliver written notice to the indemnifying party within a reasonable time of the
commencement of any such action shall not relieve such indemnifying party of any
liability to the Indemnified Person or Indemnified Party under this Section 6,
except to the extent that the indemnifying party is actually prejudiced in its
ability to defend such action. The indemnification required by this Section 6
shall be made by periodic payments of the amount thereof during the course of
the investigation or defense, as such expense, loss, damage or liability is
incurred and is due and payable.

     CONTRIBUTION.

     To the extent any indemnification by an indemnifying party is prohibited or
limited by law, the indemnifying party agrees to make the maximum contribution
with respect to any amounts for which it would otherwise be liable under Section
6 to the fullest extent permitted by law; provided, however, that (i) no
contribution shall be made under circumstances where the maker would not have
been liable for indemnification under the fault standards set forth in Section
6, (ii) no seller of Registrable Securities guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the 1933 Act) shall be
entitled to contribution from any seller of Registrable Securities who was not
guilty of such fraudulent misrepresentation, and (iii) contribution (together
with any indemnification or other obligations under this Agreement) by any
seller of Registrable Securities shall be limited in amount to the net amount of
proceeds received by such seller from the sale of such Registrable Securities.

     REPORTS UNDER THE 1934 ACT.

     With a view to making available to the Investors the benefits of Rule 144
promulgated under the 1933 Act or any other similar rule or regulation of the
SEC that may at any time permit the investors to sell securities of the Company
to the public without registration ("Rule 144"), the Company agrees to:

          make and keep public information available, as those terms are
understood and defined in Rule 144;

          file with the SEC in a timely manner all reports and other documents
required of the Company under the 1933 Act and the 1934 Act so long as the
Company remains subject to such requirements (it being understood that nothing
herein shall limit the Company's obligations under Section 4(c) of the
Securities Purchase Agreement) and the filing of such reports and other
documents is required for the applicable provisions of Rule 144; and

          furnish to each Investor so long as such Investor owns Registrable
Securities, promptly upon request, (i) a written statement by the Company that
it has complied with the reporting requirements of Rule 144, the 1933 Act and
the 1934 Act, (ii) a copy of the most recent annual or quarterly report of the
Company and such other reports and documents so filed by the Company, and (iii)
such other information as may be reasonably requested to permit the Investors to
sell such securities pursuant to Rule 144 without registration.

     ASSIGNMENT OF REGISTRATION RIGHTS.

     The rights under this Agreement shall be automatically assignable by the
Investors to any transferee of all or any portion of Registrable Securities if:
(i) the Investor agrees in writing with

                                       14
<PAGE>

the transferee or assignee to assign such rights, and a copy of such agreement
is furnished to the Company within a reasonable time after such assignment, (ii)
the Company is, within a reasonable time after such transfer or assignment,
furnished with written notice of (a) the name and address of such transferee or
assignee, and (b) the securities with respect to which such registration rights
are being transferred or assigned, (iii) following such transfer or assignment,
the further disposition of such securities by the transferee or assignee is
restricted under the 1933 Act and applicable state securities laws, (iv) at or
before the time the Company receives the written notice contemplated by clause
(ii) of this sentence, the transferee or assignee agrees in writing with the
Company to be bound by all of the provisions contained herein, (v) such transfer
shall have been made in accordance with the applicable requirements of the
Securities Purchase Agreement, and (vi) such transferee shall be an "accredited
investor" as that term defined in Rule 501 of Regulation D promulgated under the
1933 Act.

     AMENDMENT OF REGISTRATION RIGHTS.

     Provisions of this Agreement may be amended and the observance thereof may
be waived (either generally or in a particular instance and either retroactively
or prospectively), only with written consent of the Company, each of the Initial
Investors (to the extent such Initial Investor still owns Registrable
Securities) and Investors who hold a majority interest of the Registrable
Securities.  Any amendment or waiver effected in accordance with this Section 10
shall be binding upon each Investor and the Company.

7.   MISCELLANEOUS.
     -------------

a.        A person or entity is deemed to be a holder of Registrable Securities
whenever such person or entity owns of record such Registrable Securities.  If
the Company receives conflicting instructions, notices or elections from two or
more persons or entities with respect to the same Registrable Securities, the
Company shall act upon the basis of instructions, notice or election received
from the registered owner of such Registrable Securities.

b.        Any notices required or permitted to be given under the terms hereof
shall be sent by certified or registered mail (return receipt requested) or
delivered personally or by courier (including a recognized overnight delivery
service) or by facsimile and shall be effective five days after being placed in
the mail, if mailed by regular United States mail, or upon receipt, if delivered
personally or by courier (including a recognized overnight delivery service) or
by facsimile, in each case addressed to a party.  The addresses for such
communications shall be:

                  If to the Company:
                  American Telesource International, Inc.
                  12500 Network Blvd., Suite 407
                  San Antonio, Texas 78249
                  Attention: Chief Financial Officer
                  Facsimile:  (210) 558-6095
                  With copy to:

                  Patrick Tobin, Esq.
                  Jackson Walker, LLP
                  112 E. Pecan Street, Suite 2100
                  San Antonio, Texas ;78205
                  Facsimile:  (210) 978-7790

                                       15
<PAGE>

If to an Investor: to the address set forth immediately below such Investor's
name on the signature pages to the Securities Purchase Agreement.

                  With copy to:

                  Bradley D. Houser, Esq.
                  Akerman, Senterfitt & Eidson, P.A.
                  One Southeast Third Avenue
                  Miami, Florida 33131
                  Facsimile:  (305) 374-5095

          Failure of any party to exercise any right or remedy under this
Agreement or otherwise, or delay by a party in exercising such right or remedy,
shall not operate as a waiver thereof.

          This Agreement shall be governed by and construed in accordance with
the laws of the State of Delaware applicable to agreements made and to be
performed in the State of Delaware (without regard to principles of conflict of
laws).  Both parties irrevocably consent to the exclusive jurisdiction of the
United States federal courts and the state courts located in Delaware with
respect to any suit or proceeding based on or arising under this Agreement, the
agreements entered into in connection herewith or the transactions contemplated
hereby or thereby and irrevocably agree that all claims in respect of such suit
or proceeding may be determined in such courts.  Both parties irrevocably waive
the defense of an inconvenient forum to the maintenance of such suit or
proceeding.  Both parties further agree that service of process upon a party
mailed by first class mail shall be deemed in every respect effective service of
process upon the party in any such suit or proceeding.  Nothing herein shall
affect either party's right to serve process in any other manner permitted by
law.  Both parties agree that a final non-appealable judgment in any such suit
or proceeding shall be conclusive and may be enforced in other jurisdictions by
suit on such judgment or in any other lawful manner.

          This Agreement and the Securities Purchase Agreement (including all
schedules and exhibits thereto) constitute the entire agreement among the
parties hereto with respect to the subject matter hereof and thereof.  There are
no restrictions, promises, warranties or undertakings, other than those set
forth or referred to herein and therein.  This Agreement and the Securities
Purchase Agreement supersede all prior agreements and understandings among the
parties hereto with respect to the subject matter hereof and thereof.

          Subject to the requirements of Section 9 hereof, this Agreement shall
inure to the benefit of and be binding upon the successors and assigns of each
of the parties hereto.

          The headings in this Agreement are for convenience of reference only
and shall not limit or otherwise affect the meaning hereof.

          This Agreement may be executed in two or more counterparts, each of
which shall

                                       16
<PAGE>

be deemed an original but all of which shall constitute one and the same
agreement. This Agreement, once executed by a party, may be delivered to the
other party hereto by facsimile transmission of a copy of this Agreement bearing
the signature of the party so delivering this Agreement.

          Each party shall do and perform, or cause to be done and performed,
all such further acts and things, and shall execute and deliver all such other
agreements, certificates, instruments and documents, as the other party may
reasonably request in order to carry out the intent and accomplish the purposes
of this Agreement and the consummation of the transactions contemplated hereby.

          Except as otherwise provided herein, all consents and other
determinations to be made by the Investors pursuant to this Agreement shall be
made by Investors holding a majority of the Registrable Securities, determined
as if the all of the shares of Preferred Stock then  outstanding have been
converted into for Registrable Securities.

          The Company acknowledges that a breach by it of its obligations
hereunder will cause irreparable harm to each Investor by vitiating the intent
and purpose of the transactions contemplated hereby.  Accordingly, the Company
acknowledges that the remedy at law for breach of its obligations hereunder will
be inadequate and agrees, in the event of a breach or threatened breach by the
Company of any of the provisions hereunder, that each Investor shall be
entitled, in addition to all other available remedies in law or in equity, to an
injunction or injunctions to prevent or cure breaches of the provisions of this
Agreement and to enforce specifically the terms and provisions hereof, without
the necessity of showing economic loss and without any bond or other security
being required.

          The language used in this Agreement will be deemed to be the language
chosen by the parties to express their mutual intent, and no rules of strict
construction will be applied against any party.

          In the event that any provision of this Agreement is invalid or
unenforceable under any applicable statute or rule of law, then such provision
shall be deemed inoperative to the extent that it may conflict therewith and
shall be deemed modified to conform with such statute or rule of law.  Any
provision hereof which may prove invalid or unenforceable under any law shall
not affect the validity or enforceability of any other provision hereof.

          The initial number of Registrable Securities included in any
Registration Statement and each increase to the number of Registrable Securities
included therein shall be allocated pro rata among the Investors based on the
number of Registrable Securities held by each Investor at the time of such
establishment or increase, as the case may be.  In the event an Investor shall
sell or otherwise transfer any of such holder's Registrable Securities, each
transferee shall be allocated a pro rata portion of the number of Registrable
Securities included in a Registration Statement for such transferor.  Any shares
of Common Stock included on a Registration Statement and which remain allocated
to any person or entity which does not hold

                                       17
<PAGE>

any Registrable Securities shall be allocated to the remaining Investors, pro
rata based on the number of shares of Registrable Securities then held by such
Investors. For the avoidance of doubt, the number of Registrable Securities held
by an Investor shall be determined as if all Preferred Shares (including
Investment Options thereunder) and Warrants then outstanding and held by an
Investor were converted into or exercised for Registrable Securities.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

                                       18
<PAGE>

     IN WITNESS WHEREOF, the Company and the undersigned Initial Investors have
caused this Agreement to be duly executed as of the date first above written.


                         AMERICAN TELESOURCE INTERNATIONAL, INC.


                         By: /c/ H. Douglas Saathoff
                             -----------------------------
                                 H. Douglas Saathoff,
                                 Senior Vice President and
                                 Chief Financial Officer



                         RGC INTERNATIONAL INVESTORS, LDC

                         By:  Rose Glen Capital Management, L.P.,
                                Investment Manager
                              By: RGC General Partner Corp., as General Partner


                              By: /c/ Steven B. Katznelson
                                  ------------------------
                                      Steven B. Katznelson
                                      Managing Director





                                       19