ORA-04098: trigger 'APPS.PA_ADW_PROJECTS_T1' is invalid and failed re-validation

Hi

I am upgrading 11.5.10.2(with database 10.2.0.4) to R12.1.1(with database 10.2.0.4)
while applying merged patch of 6678700, adworker for pa_projects_all.xdf is failing with below error.

ALTER TABLE PA.PA_PROJECTS_ALL ADD ( AR_REC_NOTIFY_FLAG VARCHAR2(1) DEFAULT 'N' NOT NULL )

Start time for statement above is Fri Apr 19 03:34:20 PDT 2013
End time for statement above is Fri Apr 19 03:34:20 PDT 2013
Error in executing statement ALTER TABLE PA.PA_PROJECTS_ALL ADD ( AR_REC_NOTIFY_FLAG VARCHAR2(1) DEFAULT 'N' NOT NULL )
Error message is ORA-00604: error occurred at recursive SQL level 1
ORA-04098: trigger 'APPS.PA_ADW_PROJECTS_T1' is invalid and failed re-validation