How to "unlock" an ABAP object from SPAU

We have upgraded one of our test systems and find that there is a problem with a function module used by the SPAU transaction (related to OSS note 2292923/2309514). The problem makes it impossible to process objects in SPAU. We believe that a manual correction of the function module is possible, but the ABAP workbench will not allow the object to be edited because the function module is also required to be processed in SPAU. Does anyone know how to remove the "SPAU lock" from a function module ? We have had an OSS incident open with SAP for weeks, but they have not yet provided any other solution....