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                                                                    Exhibit 99.1

                TO BE INCORPORATED BY REFERENCE INTO REGISTRATION
                  STATEMENTS ON FORM S-3 (NO. 33-48168) AND ON
              FORM S-8 (NOS. 33-4436, 33-15149, 33-40800, 33-40801,
                 33-48169, 333-04913, 333-04951, and 333-67658)

                                  UNDERTAKINGS

          (a) Rule 415 Offering.

          The undersigned registrant hereby undertakes:

              (l)  To file, during any period in which offers or sales are being
          made, a post-effective amendment to this registration statement;

                   (i)   To include any prospectus required by Section 10(a)(3)
              of the Securities Act of 1933;

                   (ii)  To reflect in the prospectus any facts or events
              arising after the effective date of the registration statement (or
              the most recent post-effective amendment thereof) that,
              individually or in the aggregate, represents a fundamental change
              in the information set forth in the registration statement.
              Notwithstanding the foregoing, any increase or decrease in volume
              of securities offered (if the total dollar value of securities
              offered would not exceed that which was registered) and any
              deviation from the low or high end of the estimated maximum
              offering range may be reflected on the form of prospectus filed by
              the Commission pursuant to Rule 424(b) if, in the aggregate, the
              changes in volume and price represent no more than a 20% change in
              the maximum aggregate offering price set forth in the "calculation
              of Registration Fee" table in the effective registration
              statement;

                   (iii) To include any material information with respect to the
              plan of distribution not previously disclosed in the registration
              statement or any material change to such information in the
              registration statement;

          Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
apply if the registration statement is on Form S-3 or Form S-8 and the
information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed by the registrant pursuant to
Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are
incorporated by reference in the registration statement.

              (2)  That, for the purpose of determining any liability under the
          Securities Act of 1933, each such post-effective amendment shall be
          deemed to be a new registration statement relating to the securities
          offered therein, and the offering of such securities at that time
          shall be deemed to be the initial bona fide offering thereof.

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              (3)  To remove from registration by means of a post-effective
          amendment any of the securities being registered that remain unsold at
          the termination of the offering.

          (b) Incorporation of Documents by Reference.

          The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 (and, where applicable, each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the
Securities Exchange Act of 1934) that is incorporated by reference in the
registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

          (e) Incorporated Annual and Quarterly Reports.

          The undersigned registrant hereby undertakes to deliver or cause to be
delivered with the prospectus, to each person to whom the prospectus is sent or
given, the latest annual report to security holders that is incorporated by
reference in the prospectus and furnished pursuant to and meeting the
requirements of Rule 14a-3 or Rule 14c-3 under the Securities Exchange Act of
1934; and where interim financial information required to be presented by
Article 3 of Regulation S-X are not set forth in the prospectus, to deliver or
cause to be delivered to each person to whom the prospectus is sent or given,
the latest quarterly report that is specifically incorporated by reference in
the prospectus to provide such interim financial information.

          (h) Registration Statements on Form S-8.

          Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers and controlling
persons of the registrant, the registrant has been advised that in the opinion
of the Securities and Exchange Commission such indemnification is against public
policy as expressed in the Act and is, therefore, unenforceable. In the event
that a claim for indemnification against such liabilities (other than the
payment by the registrant of expenses incurred or paid by a director, officer or
controlling person of the registrant in the successful defense of any action,
suit or proceeding) is asserted by such director, officer or controlling person
in connection with the securities being registered, the registrant will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the Act and
will be governed by the final adjudication of such issue.