Oracle Forms

How do i disable a database trigger on forms developer 6.0? I have created a database trigger that prohibits editing of records after 15 days have elapsed since encoding the record. However, there are times when i allow editing of specific records based on valid reasons. I will try to disable the trigger temporarily on my pre-commit trigger in forms, grant update on specific columns of specific records and then enable the trigger again on post-commit. However, this does not work. Whenever I try to edit an old record, the trigger still fires. how do i solve this?

I have this code on my prre-commit:

FORMS_DDL('DISABLE SPM_IS.SPM_DAILY_OUTS_IRR_NEW ON SPM_IS.SPM_DAILY_OUTS');
FORMS_DDL('REVOKE UPDATE ON SPM_DAILY_OUTS TO SPMIS_ACC_USER');
FORMS_DDL('GRANT UPDATE (OUTAGE_TYPE, OUTAGE_CODE, OUTAGE_SUBCODE, REMARKS) ON SPM_DAILY_OUTS TO V_USER WHERE SEQ_ID = V_SEQ_ID');

Then on my post-forms-commit and post-database-commit, I have this code:

FORMS_DDL('ENABLE SPM_IS.spm_DAILY_OUTS_IRR_new ON SPM_IS.SPM_DAILY_OUTS');
FORMS_DDL('GRANT INSERT, SELECT, DELETE, UPDATE ON SPM_DAILY_OUTS TO SPMIS_ACC_USER');

Please help. Thanks