<PAGE>   1
                                                                    EXHIBIT 4.19


                                 LIMITED WAIVER

                           REGARDING CERTAIN COVENANTS
                                       AND
                          DISPOSITION OF CERTAIN ASSETS

     This LIMITED WAIVER is made and entered into as of January 24, 2000 (this
"Waiver"), among (a) ITEQ, INC., a Delaware corporation (the "Borrower"), (b)
THE GUARANTORS signatories hereto as guarantors, (c) BANKBOSTON, N.A., a
national banking association having its principal place of business at 100
Federal Street, Boston, Massachusetts 02110 (acting in its individual capacity,
"BKB"), and the other lending institutions which are or become parties to the
Credit Agreement defined below (together with BKB, the "Banks"), (d) DEUTSCHE
BANK AG, as documentation agent (the "Documentation Agent"), and (e) BANKBOSTON,
N.A., as agent for the Banks (acting in such capacity, the "Agent"). Capitalized
terms used herein without definition shall have the meanings assigned to such
terms in the Credit Agreement defined below.

     WHEREAS, the Borrower, the Guarantors, the Banks, the Documentation Agent
and the Agent have entered into Revolving Credit Agreement, dated as of October
28, 1997 (as amended and in effect from time to time, the "Credit Agreement"),
pursuant to which the Banks have extended credit to the Borrower on the terms
set forth therein;

     WHEREAS, the Borrower has requested that the Banks and the Agent suspend or
waive certain covenants and other provisions contained in the Credit Agreement
and other Loan Documents; and

     WHEREAS, the Banks and the Agent have agreed to honor such requests upon
the terms and subject to the conditions contained herein;

     NOW, THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:

     SECTION 1.  LIMITED SUSPENSION OF CERTAIN FINANCIAL COVENANTS.

     (a) The Banks and the Agent hereby agree temporarily to suspend the
Borrower's obligation to comply with Sections 8.1, 8.2, 8.3, 8.4, 8.6 and 8.7 of
the Credit Agreement until 5 p.m., Boston time, on February 29, 2000, provided,
that each of the following conditions are met:

          (i) the Borrower's EBITDA for the month of November, 1999, plus any
     non-cash losses incurred in that month in connection with the Clinton Sale
     for that month, is no less than negative $386,000,

          (ii) the Borrower's EBITDA for the month of December, 1999, is no less
     than negative $350,000, exclusive, to the extent otherwise included in the
     computation of EBITDA for the month of December, 1999,
<PAGE>   2

                                      -2-


     of any increase in the Borrower's reserve for discontinued assets
     attributable to the HMT Sale and not exceeding $4,000,000 in the aggregate,

          (iii) the Borrower's EBITDA for the month of January, 2000, is no less
     than negative $350,000, and

          (iv) the Borrower shall have provided to the Banks and the Agent,
     within 25 days following the end of each of December, 1999, and January,
     2000, a certificate signed by the Borrower's chief financial officer
     certifying as to the Borrower's compliance with minimum EBITDA condition
     for that month as set forth in this SECTION.1(a), together with the details
     thereof as reasonably requested by the Agent.

     (b) At 5:00 p.m., Boston time, on February 29, 2000, or at such earlier
time as any condition set forth in SECTION.1(a) is not met, the provisions of
SECTION.1(a) shall expire and be of no further force or effect, and the Banks
and the Agent shall thereupon have all of the rights and remedies set forth in
the Credit Agreement and the other Loan Documents as if the Borrower's
compliance with Sections 8.1, 8.2, 8.3, 8.4, 8.6 and 8.7 of the Credit Agreement
had never been suspended.


     SECTION 2. WAIVER REGARDING CERTAIN INVESTMENT RESTRICTIONS. The Banks and
the Agent hereby waive any provision of Section 7.3 of the Credit Agreement that
would otherwise restrict or prohibit:

     (a) the Borrower's investments in its International Subsidiaries (other
than International Guarantors) made prior to January 11, 2000, provided that,
after giving effect to each such investment when originally made, all of such
investments did not at that time exceed a total amount equal to 7% of
Consolidated Total Assets, and

     (b) an additional investment by the Borrower in Air-Cure Environmental GmbH
("Air-Cure") not to exceed $1,000,000 (or the equivalent thereof in
Deutschmarks), provided that such investment meets each of the following
conditions:

          (i) Air-Cure shall have obtained from an institutional lender in
     Germany (the "German Lender"), reasonably satisfactory to the Agent, a
     working capital line of credit not to exceed $1,000,000 (or the equivalent
     thereof in Deutschmarks),

          (ii) Air-Cure's obligations to the German Lender under the line of
     credit shall be secured by a prior perfected security interest in all or
     substantially all of the existing and after-acquired personal property
     assets of Air-Cure, subject only to such exceptions as are customary under
     German law and are satisfactory to the Agent,

          (iii) the Borrower shall have requested the Agent to issue under the
     Credit Agreement, and the Agent shall have issued, in favor the

<PAGE>   3
                                      -3-



     German Lender a Financial Letter of Credit, in a Maximum Drawing Amount not
     to exceed $1,000,000 (or the equivalent thereof in Deutschmarks),
     supporting Air-Cure's payment obligations to the German Lender under the
     line of credit and requiring, as a condition to draw thereunder,
     presentation of a certificate of the German Lender as to Air-Cure's payment
     default under the line of credit, together with a written assignment by the
     German Lender to the Agent, for the benefit of the Banks and the Agent, of
     all of the German Lender's right, title and interest in the line of credit
     and the collateral security therefor, and

          (iv) the documents evidencing the line of credit, the attachment,
     perfection and priority of the collateral security therefor, the Financial
     Letter of Credit, the draw certificate, the form of assignment, the related
     Letter of Credit Application, and all other documents, certificates and
     opinions relating to thereto and reasonably requested by the Agent shall be
     in form and substance reasonably satisfactory to the Agent and shall be
     executed and delivered by the parties thereto to the reasonable
     satisfaction of the Agent.

     (c) The Borrower agrees that it shall, and shall cause its Subsidiaries to,
continue to comply with the provisions of Section 7.3 of the Credit Agreement,
except as expressly modified in SECTIONS.2 (a) and (b).

     SECTION 3. LIMITED WAIVER REGARDING SALES OF CERTAIN ASSETS.

     (a) As used in this SECTION 3, the following terms have the meanings set
forth below:

     Birmingham. The tank manufacturing operations of the Borrower and its
Subsidiaries located in Birmingham, Alabama.

     Birmingham Assets. The assets of Birmingham to be sold as described on
Exhibit A attached hereto.

     Birmingham Sale. The sale by the Borrower or one or more of its
Subsidiaries of the Birmingham Assets.

     Escrow Funds. For any Subject Sale, any funds constituting the deferred
portion of the purchase price for such Subject Sale to be held in escrow,
whether pending determination of future assets or liabilities or otherwise. The
term includes, if applicable, any interest on such funds.

     Escrow Letter of Credit. For any Subject Sale, a Financial Letter of Credit
issued by the Agent, at the request of the Borrower, in favor of the buyer under
such Subject Sale or in favor of the buyer's nominee.

     Fresno. The shop built operations of the Borrower and its Subsidiaries
located in Fresno, California.

<PAGE>   4
                                      -4-


     Fresno Assets. The assets of Fresno to be sold as described on Exhibit B
attached hereto.

     Fresno Sale. The sale by the Borrower or one or more of its Subsidiaries of
the Fresno Assets.

     Graver. Graver Manufacturing Co., Inc., a Delaware corporation.

     Graver Assets. The assets and, if applicable, the issued and outstanding
capital stock of Graver and ITEQ Aviation, to be sold as described on Exhibit C
attached hereto.

     Graver Sale. The sale by the Borrower or one or more of its Subsidiaries of
the Graver Assets.

     HMT. The so-called HMT divisions of ITEQ Storage.

     HMT Assets. The assets of HMT and, if applicable, the issued and
outstanding capital stock of one or more Subsidiaries of ITEQ Storage or the
Borrower to be sold as described on Exhibit D attached hereto.

     HMT Sale. The sale by the Borrower and one or more of its Subsidiaries of
the HMT Assets.

     ITEQ Aviation. ITEQ Aviation, Inc., a Delaware corporation.

     ITEQ Storage. ITEQ Storage Systems, Inc., a Delaware corporation.

     Net Cash Proceeds. For each Subject Sale, the gross cash proceeds, net of
reasonable direct transaction costs, such as broker's fees, transfer taxes and
professional fees and expenses incurred on account of such Subject Sale. The
term does not include (a) any Escrow Funds or (b) any funds received by the
Agent pursuant to SECTION 3(a)(vi) in exchange for the issuance of an Escrow
Letter of Credit.

     Reliable. Reliable Steel, Inc., a Delaware corporation.

     Reliable Assets. The assets and, if applicable, the issued and outstanding
capital stock of Reliable, to be sold as described on Exhibit E attached hereto.

     Reliable Sale. The sale by the Borrower or one or more of its Subsidiaries
of the Reliable Assets.

     SLO The field erect operations of ITEQ Storage located in San Luis Obispo,
California.

     SLO Assets. The assets of SLO to be sold as described on Exhibit F
attached hereto.

<PAGE>   5
                                      -5-


     SLO Sale. The sale by the Borrower or one or more of its Subsidiaries of
the SLO Assets.

     Subject Assets. The Birmingham Assets, the Fresno Assets, the Graver
Assets, the HMT Assets, the Reliable Assets and the SLO Assets.

     Subject Sales. The Birmingham Sale, the Fresno Sale, the Graver Sale, the
HMT Sale, the Reliable Sale and the SLO Sale.

     (b) The Banks and the Agent hereby consent to each Subject Sale, to the
release by the Agent of the Agent's security interest in the Subject Assets
applicable to such Subject Sale, and to the release from its guaranty of any
Subsidiary which is a Guarantor and all of whose capital stock is being sold as
part of such Subject Assets, provided that, for such Subject Sale, each of the
following conditions are met:

          (i) the Net Cash Proceeds of such Subject Sale shall be no less than
     the amount set forth in the table below opposite such Subject Sale, and
     such Subject Sale shall have been completed by the date set forth in such
     table opposite such Subject Sale:


<TABLE>
<CAPTION>

        ----------------------------- ------------------------------------ --------------------------------
                                       NET CASH PROCEEDS TO BE RECEIVED
               SUBJECT SALES                      AT CLOSING                       COMPLETION DATE
        ----------------------------- ------------------------------------ --------------------------------
<S>                                             <C>                             <C>
          HMT Sale                              $38,500,000                     February 28, 2000
          Graver Sale                           $3,000,000                      February 28, 2000
          SLO Sale                              $8,500,000                      February 28, 2000
          Fresno Sale                           $1,600,000                      June 30, 2000
          Reliable Sale                         $2,500,000                      June 30, 2000
          Birmingham Sale                       $600,000                        June 30, 2000
</TABLE>


          (ii) the Net Cash Proceeds of such Subject Sale, if not paid directly
     to the Agent by the buyer, shall, upon receipt by the Borrower or any
     Subsidiary of such Net Cash Proceeds, be forthwith paid to the Agent for
     application to the Obligations,

          (iii) each of the then Total Commitment and the then maximum permitted
     outstanding amount of the Revolving Credit Loans, as set forth in the first
     sentence of Section 2.1 of the Credit Agreement, shall be permanently and
     automatically reduced by an amount equal to the Net Cash Proceeds of such
     Subject Sale, such reduction to be effective at the time at which such Net
     Cash Proceeds are first received by the Borrower or any Subsidiary,

          (iv) the Agent's security interest under the Security Documents shall
     attach, on a first perfected basis, to any non-cash proceeds of such
     Subject Sale, the Borrower hereby agreeing to, and to cause any applicable
     Subsidiary to,

<PAGE>   6
                                       -6-

               (A) deliver any such non-cash proceeds consisting of instruments
          or investment property, together with indorsements and stock powers
          executed in blank, to the Agent to hold as Collateral under the
          Security Documents,

               (B) permit the Agent to notify any escrow agent of the Agent's
          security interest, for the benefit of the Banks and the Agent, in any
          Escrow Funds, and cause the escrow agent to agree, at the time of the
          establishment of the escrow, using irrevocable instructions
          satisfactory to the Agent, to deliver the Escrow Funds, to the Agent,
          without further consent of the Borrower or such Subsidiary, for
          application to the Obligations, to such extent and at such time as
          delivery would otherwise be available to the Borrower or such
          Subsidiary under the terms of the escrow, and

               (C) take any other action as may be necessary or, in the opinion
          of the Agent, advisable for the Agent to perfect and to maintain its
          perfection and priority of such security interest,

          (v) the Agent and its counsel shall have reviewed and shall be
     reasonably satisfied with the terms and conditions of the purchase and sale
     agreement of such Subject Sale, any escrow arrangements, and all related
     documents as well as the identity of the buyer thereunder to the extent not
     previously disclosed to the Banks and the Agent prior to January 12, 2000,

          (vi) to the extent that any such purchase and sale agreement shall
     provide that payment of any portion of the purchase price is to be deferred
     as Escrow Funds, the Borrower or any applicable Subsidiary shall have used
     reasonable commercial efforts to afford the Agent the option to receive the
     Escrow Funds for application to the then outstanding Revolving Credit Loans
     (or if the Revolving Credit Loans have been paid in full, then application
     to other Obligations) in exchange for the issuance of an Escrow Letter of
     Credit and, if such option is granted to and exercised by the Agent, such
     funds shall have been received by the Agent upon issuance of the Escrow
     Letter of Credit, provided, however, that such efforts shall not be
     required of the Borrower or such Subsidiary, and the Agent may not exercise
     any such option granted, if the Maximum Drawing Amount of all Escrow
     Letters of Credit, including the Maximum Drawing Amount of any such
     proposed Escrow Letter of Credit, would exceed (A) the amount of the Total
     Commitment, minus (B) the then maximum permitted outstanding amount of
     Revolving Credit Loans as set forth in Section 2.1 of the Credit Agreement,
     minus (C) the Letter of Credit sublimit set forth in Section 3.1(a)(i) of
     the Credit Agreement,

          (vii) prior to such Subject Sale, the Banks and the Agent shall have
     received copies of, and shall be satisfied with, the results of

<PAGE>   7
                                      -7-



     appraisals and valuations by professional appraisers and valuation experts,
     to the extent so engaged by the Borrower or any of its Subsidiaries to
     support the sales price reflected in the purchase and sale agreement for
     such Subject Sale, and

          (viii) unless otherwise waived in writing by the Majority Banks, after
     otherwise giving effect to this Waiver, no Default or Event of Default
     shall have occurred and shall be continuing at the time of completion of
     such Subject Sale or would occur as a result thereof.

     (c) Upon satisfaction of the conditions set forth in SECTION 3(b) for a
Subject Sale, the Agent is instructed by the Banks (i) to provide such Uniform
Commercial Code or other releases and confirmations of releases of the Agent's
security interest in the applicable Subject Assets sold under such Subject Sale,
(ii) to provide any releases or confirmations of release of any Guarantor from
its guaranty if all of the capital stock of such Guarantor is comprised in the
Subject Sale sold under such Subject Sale, and (iii) if applicable, to deliver
to the Borrower or its nominee any certificated securities of such Guarantor's
capital stock in the possession or under the control of the Agent. The Agent
shall be entitled to assume that any factual condition set forth in SECTION
3(b), not evident from the Agent's own books and records, has been met unless
the officers of the Agent active upon the Borrower's account have actual
knowledge that such condition has not been met.

     (d) The Agent and the Banks acknowledge and agree that the Letter of Credit
sublimit set forth in Section 3.1(a)(i) of the Credit Agreement, and which is
currently $5,000,000, shall not include the Maximum Drawing Amount of any Escrow
Letter of Credit. The Maximum Drawing Amount of Escrow Letters of Credit shall
otherwise be included in computations of credit availability under the Credit
Agreement when such availability is measured by reference to the Maximum Drawing
Amounts of Letters of Credit. In the event of a drawing under an Escrow Letter
of Credit, the then maximum permitted outstanding amount of Revolving Credit
Loans, as set forth in the first sentence of Section 2.1 of the Credit
Agreement, shall be increased by the amount of such drawing. Any drawing under
an Escrow Letter of Credit shall not increase the Total Commitment.

     (e) The provisions of this SECTION 3 supersede (i) in respect of the
Birmingham Sale, the Limited Waiver Regarding Disposition of Certain Assets and
Certain Financial Covenants dated as of September 30, 1999, and (ii) in respect
of the HMT Sale, the Limited Waiver Regarding Disposition of Assets dated as of
December 8, 1999.

     SECTION 4. WAIVER FEES. The Borrower hereby agrees to pay to the Agent, for
the account of the Banks that execute this Waiver, a waiver fee equal to $15,000
in the aggregate (the "Waiver Fee"). The Waiver Fee shall be shared pro rata by
the Banks that execute this Waiver in accordance with their Commitments. The
Waiver Fee shall be nonrefundable and fully earned as of the date hereof.

<PAGE>   8
                                      -8-


     SECTION 5. CONDITIONS TO EFFECTIVENESS. This Waiver shall not become
effective unless on or prior to 5:00 p.m. Boston time on Monday, January 24,
2000, (a) the Waiver Fee shall have been paid to the Agent for the account of
each of the Banks that execute this Waiver, and (b) this Waiver shall have been
executed and delivered by the Borrower, the Guarantors, the requisite Banks and
the Agent. For purposes of Sections 1 and 2, the requisite Banks are the
Majority Banks. For purposes of Section 3, the requisite Banks are all of the
Banks. Any Exhibit relating to a Subject Sale referred to in Section 3 may be
delivered by the Borrower after this Waiver has become effective, but the
provisions of Section 3 applicable to such Subject Sale will not become
effective until the Agent has received and approved such Exhibit.

     SECTION 6. REPRESENTATIONS AND WARRANTIES. The Borrower hereby represents
and warrants to the Banks and the Agent as follows:

     SECTION 6.1. REPRESENTATIONS AND WARRANTIES IN CREDIT AGREEMENT. Each of
the representations and warranties of the Borrower contained in the Credit
Agreement as modified hereby or in any document or instrument delivered pursuant
to or in connection with the Credit Agreement as modified hereby are true as of
the date hereof (except to the extent of changes resulting from transactions
contemplated or permitted by the Credit Agreement and changes occurring in the
ordinary course of business which singly or in the aggregate are not materially
adverse, or to the extent that such representations and warranties relate solely
and expressly to an earlier date) and, taking into account this Waiver, no
Default or Event of Default has occurred and is continuing.

     SECTION.6.2. AUTHORITY, NO CONFLICTS, ETC. The execution, delivery and
performance of this Waiver and the transactions contemplated hereby (i) are
within the corporate authority of the Borrower and the Guarantors, (ii) have
been duly authorized by all necessary corporate proceedings, (iii) do not
conflict with or result in any material breach or contravention of any provision
of law, statute, rule or regulation to which the Borrower or any Guarantor is
subject or any judgment, order, writ, injunction, license or permit applicable
to the Borrower or Guarantors so as to materially adversely affect the assets,
business or any activity of the Borrower or Guarantors, and (iv) do not conflict
with any provision of the corporate charter or bylaws of the Borrower or
Guarantors or any agreement or other instrument binding upon them. The
execution, delivery and performance of this Waiver will result in valid and
legally binding obligations of the Borrower and Guarantors enforceable against
each in accordance with the respective terms and provisions hereof.

     SECTION 7. RATIFICATION, ETC. This Waiver is limited to the waivers set
forth herein and upon the terms and subject to the conditions contained herein.
Except as expressly stated herein, the Credit Agreement, the other Loan
Documents and all documents, instruments and agreements related thereto are
hereby ratified and confirmed in all respects and shall continue in full force
and effect. This Waiver is a Loan Document.

<PAGE>   9
                                      -9-


     SECTION 8. RELEASE. In order to induce the Agent and the Banks to enter
into this Waiver, each of the Borrower and the Guarantors acknowledges and
agrees that: (i) neither the Borrower nor any Guarantor has any claim or cause
of action against the Agent or any Bank (or any of its respective directors,
officers, employees or agents); (ii) neither the Borrower nor any Guarantor has
any offset right, counterclaim or defense of any kind against any of their
respective obligations, indebtedness or liabilities to the Agent or any Bank;
and (iii) each of the Agent and the Banks has heretofore properly performed and
satisfied in a timely manner all of its obligations to the Borrower and each
Guarantor. The Borrower and the Guarantors wish to eliminate any possibility
that any past conditions, acts, omissions, events, circumstances or matters
would impair or otherwise adversely affect any of the Agent's and the Banks'
rights, interests, contracts, collateral security or remedies. Therefore, each
of the Borrower and the Guarantors unconditionally releases, waives and forever
discharges (A) any and all liabilities, obligations, duties, promises or
indebtedness of any kind of the Agent or any Bank to either the Borrower and any
Guarantor, except the obligations to be performed by the Agent or any Bank on or
after the date hereof as expressly stated in this Waiver, the Credit Agreement
and the other Loan Documents, and (B) all claims, offsets, causes of action,
suits or defenses of any kind whatsoever (if any), whether arising at law or in
equity, whether known or unknown, which the Borrower or any Guarantor might
otherwise have against the Agent, any Bank or any of its directors, officers,
employees or agents, in either case (A) or (B), on account of any past or
presently existing condition, act, omission, event, contract, liability,
obligation, indebtedness, claim, cause of action, defense, circumstance or
matter of any kind.

     SECTION 9. COUNTERPARTS. This Waiver may be executed in any number of
counterparts, which together shall constitute one instrument.

     SECTION 10. GOVERNING LAW. THIS WAIVER SHALL BE A CONTRACT UNDER THE LAWS
OF THE COMMONWEALTH OF MASSACHUSETTS, SHALL FOR ALL PURPOSES BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE INTERNAL LAWS OF SAID JURISDICTION, WITHOUT
REFERENCE TO CONFLICTS OF LAW, AND IS INTENDED TO TAKE EFFECT AS A SEALED
INSTRUMENT.



<PAGE>   10







     IN WITNESS WHEREOF, the parties hereto have executed this Waiver as an
instrument under seal to be effective as of the date first above written.

THE BORROWER:

ITEQ, INC.


By:/s/  MARK E. JOHNSON
  ------------------------------
     Name:  Mark E. Johnson
     Title: Chairman




<PAGE>   11







THE GUARANTORS:

ITEQ MANAGEMENT COMPANY
EXELL, INC. (a Delaware corporation which is
 successor by merger to EXELL. INC., a Texas
 corporation)
ITEQ TANK SERVICES, INC. (successor by
 merger to HMT TANK SERVICE, INC.)
RELIABLE STEEL, INC.
AIR-CURE DYNAMICS, INC.
AMEREX INDUSTRIES, INC.
OHMSTEDE, INC.
INTEREL ENVIRONMENTAL
 TECHNOLOGIES, INC.
ALLIED INDUSTRIES, INC.
ITEQ CONSTRUCTION SERVICES, INC.
 (f/k/a HMT CONSTRUCTION SERVICES,
 INC.)
ITEQ INTELLECTUAL PROPERTIES, INC.
 (f/x/a AIX INTELLECTUAL PROPERTIES,
 INC.)
ITEQ INVESTMENTS, INC. (f/k/a
 ASTROTECH INVESTMENTS, INC.)
TEXOMA TANK COMPANY, INC.
ITEQ STORAGE SYSTEMS, INC. (f/k/a
 BROWN-MINNEAPOLIS TANK &
 FABRICATING CO., successor by merger to
 HMT, INC., HMT SENTRY SYSTEMS, INC.
 and TRUSCO TANK, INC.)
GRAVER MANUFACTURING CO., INC.
 (f/k/a GRAVER HOLDING COMPANY,
 successor by merger to GRAVER TANK &
 MFG. CO., INC., GRAVER TANK
 INTERNATIONAL, INC., GRAVER POWER,
  INC., and GRAVER TANK & VESSEL, INC.)
G.L.M. ACQUISITION, L.L.C.


By:/s/  MARK E. JOHNSON
  -----------------------------
     Name:  Mark E. Johnson
     Title: Chairman


<PAGE>   12
THE LENDERS:

BANKBOSTON, N.A.,
 individually and as Agent


By: /s/  VIRGINIA W. DENNETT
  --------------------------------
  Name:  Virginia W. Dennett
  Title: Vice President



DEUTSCHE BANK AG,
 individually and as Documentation Agent


By: /s/  MARGARET S. CHEAVER
  ---------------------------------
  Name:  Margaret S. Cheaver
  Title: Managing Director


By: /s/  ROBERT C. WHEELER
  ---------------------------------
  Name:  Robert C. Wheeler
  Title: Director



BANK OF SCOTLAND


By: /s/  ANNIE GLYNN
  ----------------------------------
  Name:  Annie Glynn
  Title: Senior Vice President



BANK ONE, TEXAS, N.A.


By:  /s/  BRADLEY C. PETERS
  ----------------------------------
  Name:  Bradley C. Peters
  Title: Vice President

<PAGE>   13





PARIBAS (f/k/a Banque Paribas)


By:/s/  SCOTT CLINGAN
  -----------------------------------
  Name:  Scott Clingan
  Title: Director


By: /s/  LARRY ROBINSON
  -----------------------------------
  Name:  Larry Robinson
  Title: Vice President



COMERICA BANK


By: /s/  T. BANCROFT MATTEI
  -----------------------------------
  Name:  T. Bancroft Mattei
  Title: Account Officer



THE FUJI BANK, LIMITED


By: /s/  RAYMOND VENTURA
  -----------------------------------
  Name:  Raymond Ventura
  Title: Vice President & Manager



HIBERNIA NATIONAL BANK


By: /s/  CHRISTOPHER PITRE
  -----------------------------------
  Name:  Christopher Pitre
  Title: Vice President



BANK OF AMERICA, N.A. (f/k/a NationsBank, N.A.)


By: /s/  WILLIAM E. LIVINGSTONE, IV
  -----------------------------------
  Name:  William E. Livingstone, IV
  Title: Managing Director


<PAGE>   14






UNION BANK OF CALIFORNIA, N.A.


By: /s/  JOEL STEINER
  -----------------------------------
  Name:  Joel Steiner
  Title: Vice President



CHASE BANK TEXAS, NATIONAL ASSOCIATION (f/k/a Texas Commerce Bank, N.A.)


By:/s/  BRUCE A. SHILCUTT
  -----------------------------------
  Name:  Bruce A. Shilcutt
  Title: Vice President