Filed by Tumbleweed Communications Corp. Pursuant to Rule 425
                                              Under the Securities Act of 1933
                                      And Deemed Filed Pursuant to Rule 14a-12
                                     Under the Securities Exchange Act of 1934
                                               Subject Company: Valicert, Inc.
                                                 Commission File No: 000-31109


         On February 18, 2003, Tumbleweed Communications Corp. and Valicert,
Inc. issued a joint press release announcing that Tumbleweed and Valicert had
entered into an Agreement and Plan of Reorganization and Merger, dated as of
February 18, 2003. The text of the joint press release follows.

         Tumbleweed and Valicert Announce Merger Agreement

To Create Best-of-Breed Enterprise-Class Secure Messaging Suite

REDWOOD CITY and MOUNTAIN VIEW, CA - February 18, 2003 - Tumbleweed(R)
Communications Corp. (Nasdaq: TMWD), a leading provider of secure messaging
applications for businesses and government agencies using the Internet, and
Valicert, Inc. (Nasdaq: VLCT), a leading provider of software that securely
connects companies with their customers, suppliers and partners across the
financial value chain, today announced the signing of a definitive merger
agreement. Pending shareholder and regulatory approvals, Tumbleweed will
acquire all of the outstanding shares of Valicert, Inc. in a stock-for-stock
transaction. As approved by the Boards of Directors of each company, the
merger calls for each share of Valicert common stock to be exchanged for 0.385
shares of Tumbleweed common stock, or approximately 9.8 million shares, which
will represent approximately 24% of Tumbleweed's outstanding stock post
merger. Based on today's closing price for Tumbleweed's stock, the market
value of the transaction is approximately $14.3 million. Tumbleweed will also
expand its current Board of Directors to add a Valicert-selected Director. The
purchase transaction is expected to close in the second or third quarter,
depending upon regulatory review, and to be accretive to pro forma earnings by
the end of Tumbleweed's fiscal year.

"Both Tumbleweed and Valicert deliver solutions that allow businesses and
government agencies to automate and move their business processes online,"
said Jeff Smith, Chairman and CEO of Tumbleweed Communications. "Our companies
have attained deep domain expertise in adjacent and complementary application
areas: Tumbleweed is a leading provider of secure messaging; Valicert is a
leading provider of secure data transfer and certificate validation. We expect
that the combination will be formidable force in the marketplace, and will
expand our total available market without dramatically increasing the cost of
sales," Smith continued.

"We are excited to join forces with Tumbleweed," said John Vigouroux,
President and Chief Executive Officer of Valicert. "Having established
ourselves as the premier provider of secure data transfer and certificate
validation, merging with Tumbleweed will bring an even more robust set of
solutions to our mutual customers. Our complementary offerings serve a similar
customer set in the Finance, Healthcare, and Government sectors. Our
customers, partners, employees and shareholders will all benefit from the
experienced management team that Tumbleweed has assembled, and the stability
that will come from the stronger financial position we expect from our
combined company. We remain committed to supporting our customers and partners
around the world. We believe that by merging with Tumbleweed, we can achieve
the critical mass that accrues to the best-of-breed suppliers of
mission-critical enterprise solutions," Vigouroux added.

After the merger is concluded, John Vigouroux will join Tumbleweed's executive
staff as Senior Vice President and General Manager of the Valicert division of
Tumbleweed. Vigouroux will report to Doug Sabella, President and Chief
Operating Officer of Tumbleweed Communications. Current Valicert employees
will continue to report to Vigouroux in the new division.

"We expect to achieve operating profitability on a combined basis in the
fourth quarter of this year," said Doug Sabella, President and Chief Operating
Officer of Tumbleweed Communications. "We see strong synergies between our
products, markets, customers and organizations. The larger corporate size and
stronger finances of the combined company will offer the increased market
share, product breadth and financial stability that customers are seeking. The
combined revenue of both companies will complement anticipated synergies on
the cost side, such as improved sales efficiencies, reduced public-company
reporting costs, and additional potential savings from the elimination of
redundant infrastructure, including leased office space. Finally, since our
headquarters are only a few miles apart, consolidation is anticipated to be
quick and frugal," Sabella concluded.

Conference Call Information
Tumbleweed and Valicert will host a joint conference call with the investment
community tomorrow morning, Wednesday February 19 at 5:30 AM PT/8:30 AM ET to
discuss the proposed merger. This call will be made available to all
interested parties by telephone at (888) 413-5356, conference number 76948,
and via live webcast on Tumbleweed's website at http://www.tumbleweed.com,
under Company heading, Investor Relations; and on Valicert's website at
http://www.valicert.com in the Investor section of the site. A replay of the
conference call will be available for 30 days on both websites, and by
telephone at (763) 925-2510, conference number 76948.


About Tumbleweed
Tumbleweed is a leading provider of secure messaging applications for
businesses and government agencies using the Internet. Tumbleweed's robust
policy-based platform empowers organizations to safely share and protect
critical information, increase customer loyalty and privacy and dramatically
reduce costs. Tumbleweed is trusted by hundreds of blue-chip customers
including American Express, Amgen Inc., Bank of America Securities, Catholic
Healthcare West, ChevronTexaco Corp., Dell Computer Corporation, National City
Corporation, Oppenheimer Funds, Inc., The Regence Group (Blue Cross/Blue
Shield), TD Waterhouse Investor Services, Inc., the U.S. Department of Energy
and the U.S. Navy. Tumbleweed Communications was founded in 1993 and is
headquartered in Redwood City, California. More information about Tumbleweed
is available on the World Wide Web at www.tumbleweed.com.

About Valicert
Valicert is a leading provider of secure communications and authentication
software for file transfer, financial messaging, and business process
integration over the Internet. Enterprises and government agencies use
Valicert products to accelerate their financial and corporate supply chain
processes and to exchange sensitive data inside and outside of their
organizations. Valicert customers enjoy significant cost savings and
efficiencies by migrating from private networks and paper processes to the
Internet. Valicert is trusted by hundreds of blue-chip customers including ABN
AMRO, Aetna, Blue Cross/Blue Shield of Kansas City, Freightliner, Hitachi, JP
Morgan Chase, NTT Communications, Royal Bank of Scotland, Sears Roebuck and
Co., State of Washington, and several branches of the US Department of
Defense. Valicert was founded in 1996 and is headquartered in Mountain View,
California. More information about Valicert is available on the World Wide Web
at www.valicert.com.

ADDITIONAL INFORMATION AND WHERE TO FIND IT

Tumbleweed intends to file a registration statement on Form S-4 in connection
with the transaction, and Tumbleweed and Valicert intend to mail a joint proxy
statement/prospectus to their respective stockholders in connection with the
transaction. Investors and security holders of Tumbleweed and Valicert are
urged to read the joint proxy statement/prospectus when it becomes available
because it will contain important information about Tumbleweed, Valicert and
the transaction. Investors and security holders may obtain a free copy of the
joint proxy statement/prospectus (when it is available) at the SEC's web site
at www.sec.gov. A free copy of the joint proxy statement/prospectus may also
be obtained from Tumbleweed or Valicert. Tumbleweed and its executive officers
and directors may be deemed to be participants in the solicitation of proxies
from the stockholders of Tumbleweed and Valicert in favor of the transaction.
Information regarding the interests of Tumbleweed's officers and directors in
the transaction will be included in the joint proxy statement/prospectus.
Valicert and its executive officers and directors also may be deemed to be
participants in the solicitation of proxies from the stockholders of
Tumbleweed and Valicert in favor of the transaction. Information regarding the
interests of Valicert's officers and directors in the transaction will be
included in the joint proxy statement/prospectus. In addition to the
registration statement on Form S-4 to be filed by Tumbleweed in connection
with the transaction, and the joint proxy statement/prospectus to be mailed to
the stockholders of Tumbleweed and Valicert in connection with the
transaction, each of Tumbleweed and Valicert file annual, quarterly and
special reports, proxy and information statements, and other information with
the SEC. Investors may read and copy any of these reports, statements and
other information at the SEC's public reference rooms located at 450 5th
Street, N.W., Washington, D.C., 20549, or any of the SEC's other public
reference rooms located in New York and Chicago. Investors should call the SEC
at 1-800-SEC-0330 for further information on these public reference rooms. The
reports, statements and other information filed by Tumbleweed and Valicert
with the SEC are also available for free at the SEC's web site at www.sec.gov.
A free copy of these reports, statements and other information may also be
obtained from Tumbleweed at their website www.tumbleweed.com or Valicert at
their website at www.valicert.com.


SAFE HARBOR STATEMENT

Tumbleweed and Valicert caution that forward-looking statements contained in
this press release are based on current plans and expectations, and that a
number of factors could cause the actual results to differ materially from the
guidance given at this time. These factors are described in the Safe Harbor
statement below.

Except for the historical information contained herein, the matters discussed
in this press release may constitute forward-looking statements that involve
risks and uncertainties that could cause actual results to differ materially
from those projected. These statements include those concerning the
consummation of the acquisition and, if consummated, its potential benefits
and effects, including but not limited to any expectations that the
transaction will be accretive and any expectations as to profitability of the
combined company. In some cases, forward-looking statements can be identified
by terminology such as "may," "will," "should," "potential," "continue,"
"expects," "anticipates," "intends," "plans," "believes," "estimates," and
similar expressions. For further cautions about the risks of investing in
Tumbleweed or Valicert, we refer you to the documents Tumbleweed and Valicert
file from time to time with the Securities and Exchange Commission,
particularly Tumbleweed's Form 10-K filed March 29, 2002 and Form 10-Q filed
November 14, 2002, Valicert's Form 10-K filed April 1, 2002 and Form 10-Q
filed November 13, 2002, and the registration statement relating to the
acquisition to be filed subsequently. In this regard, investors are cautioned
that the acquisition may not be consummated on the terms proposed or at all,
and, if consummated, the combined companies will be subject to numerous risks
and uncertainties, including, but not limited to, the risks inherent in
acquisitions of technologies and businesses, including the integration of
separate workforces, the timing and successful completion of technology and
product development through production readiness, integration of such
technologies and businesses into the combined company, unanticipated
expenditures, changing relationships with customers, suppliers and strategic
partners, and other factors.

Tumbleweed and Valicert assume no obligation to update information contained
in this press release, including for example guidance regarding future
performance, which represents the companies' expectations only as of the date
of this release and should not be viewed as a statement about the companies'
expectations after such date. Although this release may remain available on
the companies' websites or elsewhere, its continued availability does not
indicate that the companies are reaffirming or confirming any of the
information contained herein.

                                     # # #


For further information, please contact:

Tumbleweed                             Valicert
Bill Bradford                          David Jevans
Vice President, Marketing              Senior VP Marketing & Corp. Development
650-216-2064                           650-567-5616
bill.bradford@tumbleweed.com           davej@valicert.com