How to add a new partner to a Marketing Campaign

Hi, I m trying to add new partner to the parties involved..

i m using CLASS: CL_CRM_MKTPL_APPL_BASE

and method:  IF_CRM_MKTGS_PAR_DATA_PROVIDER~PARTNER_CREATE but we cant do it!!!

DATA : LO_PARTNER TYPE REF TO CL_CRM_MKTPL_APPL_BASE .

        LO_PARTNER = CL_CRM_MKTPL_APPL_BASE=>GET_INSTANCE( ).

        CHECK LO_PARTNER IS BOUND.

        LO_PARTNER->PARTNER_CREATE(

         EXPORTING

            IV_GUID            = LV_GUID

            IT_PARTNER         = LT_PARTNERS

            IV_SUPPRESS_PARDET = LV_SUPPRESS_PARDET

         IMPORTING

            EV_ERROR_OCCURED   = LV_ERROR_OCCURED

            ET_MESSAGES        = LT_MESSAGES ).

        IF sy-subrc = 0.

          CALL METHOD LO_PARTNER->save

            EXCEPTIONS

              failed = 1

              OTHERS = 2

please help!!!