<PAGE>   1
                                                                   EXHIBIT 10.22

               Confidential Materials omitted and filed separately
    with the Securities and Exchange Commission. Asterisks denote omissions.

       FIFTH AMENDMENT TO PROGRESS SOFTWARE APPLICATION PARTNER AGREEMENT

FIFTH AMENDMENT to the Progress Software Corporation Application Partner
Agreement is effective as of the 18 day of February, 1999 ("Effective Date"), by
and between Progress Software Corporation, a Massachusetts corporation with its
principal place of business at 14 Oak Park, Bedford, Massachusetts 01730 ("PSC")
and Security Dynamics Inc., a Massachusetts corporation with its principal place
of business at 36 Crosby Drive, Bedford, Massachusetts 01730 ("AP").

         WHEREAS, PSC and AP entered into a Progress Software Application
Partner Agreement effective as of December 5, 1994 (the "Agreement"); and

         WHEREAS, PSC and AP previously amended the Agreement by entering into
the Progress Software Application Partner Agreement Addendum effective as of
December 5, 1994 (the "Addendum") and a subsequent amendment to the Agreement
dated as of October 19, 1995 (the "Amendment");

         WHEREAS, PSC and AP entered into a Second Amendment to the Agreement
dates as of November 29, 1995 (the "Second Amendment") which completely
superseded the terms and conditions of the earlier Addendum and Amendment and
specified new special pricing and distribution terms and conditions in an
Attachment A relating to certain PSC products distributed by AP or AP's
distributors in conjunction with AP's PROGRESS(R)-based applications; and

         WHEREAS, PSC and AP entered into a Third Amendment to the Agreement
dated as of November 15, 1996 (the "Third Amendment") specifying certain
additional modifications to the terms and conditions of the Agreement and
replacing the Attachment A incorporated by reference into the Second Amendment
with a new Attachment A including modified special pricing and distribution
terms and conditions relating to certain PSC products distributed by AP or AP's
distributors in conjunction with AP's PROGRESS(R)-based applications; and

         WHEREAS, PSC and AP entered into a Fourth Amendment to the Agreement
dated as of April 1, 1998 (the "Fourth Amendment") identifying the PSC products
that AP has the right to distribute to accomplish the AP customer configuration
for AP's PROGRESS(R)-based application.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which is hereby acknowledged, the parties hereto agree as follows:

1.       AP has developed PKI Products (Public Key Infrastructure) currently
         known as Keon that, like the current ACE/Server application, may
         incorporate the Progress Data-base. PSC hereby grants, and AP accepts,
         a license to use, distribute, OEM and sub-license the Progress
         Data-base in AP's PKI Products listed below. Such list may be updated
         from time to time upon written agreement of the parties. AP will
         continue to sell the ACE/Server application, along with the PKI
         Products. AP will sell the PKI Products in user packs as opposed to
         user levels as is currently done with the ACE/Server application. No
         further Progress products will be required at this time for the PKI
         Products than is required for the ACE/Server application.

2.       Sales of the PKI Products that contain the Progress Data-base will be
         deducted from AP's pre-payment to PSC at the same royalty rate as the
         ACE/Server application as specified in the Fourth Amendment.






<PAGE>   2



3.       The PKI Products presently include the Products known under the
         following names:

                  Keon
                  Keon Unix Platform Security
                  Keon OEM Certificate Server

         The parties agree that the Keon OEM Certificate Server product is to be
         distributed by AP and RSA Data Securities ("RSA"), a wholly owned
         subsidiary of AP, through RSA's OEM channel. Sales of the OEM product
         will be deducted from AP's pre-payment to PSC at the same royalty rate
         as the ACE/Server application as specified in the Fourth Amendment.

4.       AP will provide an updated price list for AP's Keon product, as well as
         a price list for RSA's OEM product when available, a current copy of
         which is attached hereto as Exhibits A and B. The parties do not
         anticipate any significant variations from the price lists currently
         provided to the final price list currently under final review. AP
         agrees to provide to PSC any new or updated price lists that may be
         later developed by AP or RSA as required under the Agreement.

5.       Any customer upgrades from the current ACE/Server application to the
         new PKI Products will be handled through AP's standard maintenance
         practices, and will be deducted from AP's pre-payment to PSC at the
         current rate applicable for such maintenance royalties.

6.       AP will continue to provide to PSC monthly reports, and will itemize
         separately in such reports the ACE/Server application sales, PKI
         Product sales, RSA and AP OEM sales, and any maintenance sales relating
         thereto.

7.       The term of this Fifth Amendment shall commence as of the Effective
         Date defined above, and shall continue in force until the expiration
         date as specified in Section 6 of the Third Amendment.

8.       Except as modified or amended by this Fifth Amendment, the terms and
         conditions of the Agreement (as previously amended by the Fourth, Third
         and Second Amendments thereto) shall remain in effect until the
         termination of the Agreement. No other modifications or additions are
         made to the Agreement. The Agreement, Fifth, Fourth, Third, Second and
         First Amendments constitutes the entire agreement between the parties
         with respect to the subject matter hereof. In the event of conflict
         among the terms and conditions of the Agreement, the Second Amendment,
         Third Amendment, Fourth Amendment, or this Fifth Amendment, the order
         of precedence shall be: first, this Fifth Amendment, second the Fourth
         Amendment, third, the Third Amendment, fourth, the Second Amendment
         (which completely supersedes the earlier Addendum and Amendment) and
         fifth and finally, the Agreement.

         IN WITNESS WHEREOF, this Fifth Amendment has been executed under seal
for and on behalf of each of the parties hereto by their duly authorized
representative as of the date first set forth above.

PROGRESS SOFTWARE CORPORATION             SECURITY DYNAMICS TECHNOLOGIES, INC.


By: /s/ Paul J. Maddalum                  By: /s/ James C. Bandanza
Name:  Paul J. Maddalum                   Name:  James C. Bandanza
Title:  V.P. North American Sales         Title:  Director - Business Management


<PAGE>   3



          Confidential Materials omitted and filed separately with the
        Securities and Exchange Commission. Asterisks denote omissions.


                                   Exhibit "A"
                        Security Dynamics U.S. Price List

Effective January 1999           SECURITY DYNAMICS U.S. PRICE LIST

KEON SOLUTIONS

<TABLE>
<CAPTION>
KEON                                                 MAINTENANCE
<S>                                     <C>          <C>
Model Number: KEON                                   Maintenance Model Number: KEON MAINT
Platform Selection (Identify Platform)  IBM AIX
                                        Sun Solaris
                                        HP UNIX

Encryption Level (Identify Level)       40 bit
                                        56 bit
</TABLE>

<TABLE>
<CAPTION>
                                            US LIST PRICE        SecurCare Plus         SecurCare Extended
<S>                                         <C>                  <C>                    <C>
25 User Packs                                   [**]                [**]                             [**]
50 User Packs                                   [**]                [**]                             [**]
100 User Packs                                  [**]                [**]                             [**]
250 User Packs                                  [**]                [**]                             [**]
500 User Packs                                  [**]                [**]                             [**]
1000 User Packs                                 [**]                [**]                             [**]
2500 User Packs                                 [**]                [**]                             [**]
5000 User Packs                                 [**]                [**]                             [**]
10000 User Packs                                [**]                [**]                             [**]
25000 User Packs                                [**]                [**]                             [**]
50000 User Packs                                [**]                [**]                             [**]
50000+ User Packs                               [**]
</TABLE>

<PAGE>   4


          Confidential Materials omitted and filed separately with the
        Securities and Exchange Commission. Asterisks denote omissions.

                                            Exhibit "A"
                                  Security Dynamics U.S. Price List

Effective January 1999           SECURITY DYNAMICS U.S. PRICE LIST


<TABLE>
<CAPTION>
KEON UNIX PLATFORM SECURITY                                    MAINTENANCE
<S>                                      <C>                   <C>
Model Number: KEON UPS                                         Maintenance Model Number: KEON UPS MAINT
Platform Selection (Identify Platform)   IBM AIX
                                         Sun Solaris
                                         HP UNIX
                                         DEC UNIX
                                         Sinix
                                         NCR
                                         SGI Irix

Encryption Level (Identify Level)        40 bit
                                         56 bit
</TABLE>

<TABLE>
<CAPTION>
                                    US LIST PRICE       SecurCare Plus         SecurCare Extended
<S>                                 <C>                 <C>                    <C>
1 Server Pack                              [**]               [**]                    [**]
5 Server Pack                              [**]               [**]                    [**]
10 Server Pack                             [**]               [**]                    [**]
25 Server Pack                             [**]               [**]                    [**]
100 Server Pack                            [**]               [**]                    [**]
250 Server Pack                            [**]               [**]                    [**]
500 Server Pack                            [**]               [**]                    [**]
1000 User Packs                            [**]               [**]                    [**]

10 Workstation Pack                        [**]               [**]                    [**]
100 Workstation Pack                       [**]               [**]                    [**]
250 Workstation Pack                       [**]               [**]                    [**]
500 Workstation Pack                       [**]               [**]                    [**]
1000 Workstation Pack                      [**]               [**]                    [**]
</TABLE>

++Previously branded BoKS


<PAGE>   5


          Confidential Materials omitted and filed separately with the
        Securities and Exchange Commission. Asterisks denote omissions.

                                            EXHIBIT "B"

Keon Certificate Server

The proposed end user pricing for Bobcat PKI will be [**] per user at suggested
retail price with a declining scale for increasing volume. The proposed pricing
for OEMs is a [**] discount off of the end user pricing.

The scale declining scale proposed for volume pricing is as follows:

         Table 4: Volume pricing scale

<TABLE>
<CAPTION>
                      Volume                      Price Per User
<S>                 <C>                           <C>
                       [**]                          [**]
                       [**]                          [**]
                       [**]                          [**]
                       [**]                          [**]
                       [**]                          [**]
                       [**]                          [**]
                       [**]                          [**]
</TABLE>