EX-99.23(d)(99)


                                    AMENDMENT
                                       TO
                        INVESTMENT SUB-ADVISORY AGREEMENT
                                     BETWEEN
                     JACKSON NATIONAL ASSET MANAGEMENT, LLC
                                       AND
                      GOLDMAN SACHS ASSET MANAGEMENT, L.P.

     This AMENDMENT is made by and between  JACKSON  NATIONAL ASSET  MANAGEMENT,
LLC, a Michigan  limited  liability  company and registered  investment  adviser
("Adviser"),  and GOLDMAN SACHS ASSET  MANAGEMENT,  L.P., a limited  partnership
organized  under the laws of the state of  Delaware  and  registered  investment
adviser ("Sub-Adviser").

     WHEREAS,   the  Adviser  and   Sub-Adviser   entered  into  an   Investment
Sub-Advisory  Agreement dated as of May 2, 2005  ("Agreement"),  whereby Adviser
appointed Sub-Adviser to provide certain  sub-investment  advisory services to a
investment portfolio of the JNL Series Trust; and

     WHEREAS,  pursuant  to  the  Agreement,  the  Adviser  agreed  to  pay  the
Sub-Adviser  for  the  services   provided  and  the  expenses  assumed  by  the
Sub-Adviser a sub-advisory fee as set forth on Schedule B to the Agreement,  and
the  Sub-Adviser  agreed to accept such  sub-advisory  fee as full  compensation
under the Agreement for such services and expenses; and

     WHEREAS,  the  Adviser  desires  to appoint  Sub-Adviser  to  provide,  and
Sub-Adviser has agreed to provide,  additional  sub-investment advisory services
to a new investment portfolio of the JNL Series Trust,  effective upon execution
or, if later,  the date that initial  capital for such  investment  portfolio is
first provided.

     NOW THEREFORE,  in consideration of the mutual covenants herein  contained,
the parties hereby agree to amend the Agreement as follows:

     1.   Schedule A to the  Agreement  is hereby  deleted  and  replaced in its
          entirety with Schedule A dated May 1, 2006, attached hereto.

     2.   Schedule B to the  Agreement  is hereby  deleted  and  replaced in its
          entirety with Schedule B dated May 1, 2006, attached hereto.

     IN WITNESS  WHEREOF,  the  Adviser  and the  Sub-Adviser  have  caused this
Amendment to be executed as of this 1st day of May, 2006.

JACKSON NATIONAL ASSET              GOLDMAN SACHS ASSET
MANAGEMENT, LLC                     MANAGEMENT, L.P.


By:                                 By:

Name:    MARK D. NERUD              Name:

Title:   CHIEF FINANCIAL OFFICER    Title:





                                   SCHEDULE A
                                     (FUNDS)


                   JNL/GOLDMAN SACHS SHORT DURATION BOND FUND
                      JNL/GOLDMAN SACHS MID CAP VALUE FUND







                                   SCHEDULE B
                                DATED MAY 1, 2006

                                 (Compensation)

                   JNL/GOLDMAN SACHS SHORT DURATION BOND FUND

                           AVERAGE DAILY NET ASSETS           ANNUAL RATE

                           $0 TO $100 MILLION:                   .20%
                           $100 TO $250 MILLION:                 .17%
                           $250 TO $500 MILLION:                 .15%
                           OVER $500 MILLION:                    .12%


                      JNL/GOLDMAN SACHS MID CAP VALUE FUND

                           AVERAGE DAILY NET ASSETS           ANNUAL RATE

                           $0 TO $100 MILLION:                   .50%
                           $OVER $100 MILLION:                   .45%