Dynamic procedure works in PB9 not in PB12

I’m getting this error in a pb script in PB12, but not in
PB9.  Details below  Li_rv is declared as an integer in my script. Can someone tell me what to change to get this to run?

  SQLSTATE = 42000

Microsoft SQL Native Client

Must declare the scalar variable "@li_rv".

This is the point at which the error occurs.

SQLDA.SetDynamicParm(1, ldc_reserve_id)

EXECUTE DYNAMIC
stu_sp_waitlist USING DESCRIPTOR SQLDA;

This is the setup prior to the execute.

Integer li_rv

DECLARE stu_sp_waitlist DYNAMIC PROCEDURE FOR SQLSA;

ls_sqlsa = "execute @li_rv = stu_sp_waitlist
@an_ReserveID=?"

PREPARE SQLSA FROM :ls_sqlsa USING SQLCA;

DESCRIBE SQLSA INTO SQLDA;

Here is the declaration of the procedure.

create  proc
dbo.Stu_sp_Waitlist    (@an_ReserveID, numeric(10))

as

declare  @errno          int,

              @li_Enrolled    int,

              @li_MaxEnrolled int,

                @li_Auditing    int,

          @li_MaxAudit    int

/*