The exit routine must be located in the link-pack area: PLPA, FLPA, or MLPA. RACF® initialization locates the exit at IPL time and places the exit address in the RACF communication vector table (RCVT). If RACF does not find the exit in the link-pack area, it sets the RCVT fields pointing to the exit to zero.

If you change the exit, you must re-IPL MVS™ for the changes to take effect.