Patch 5307530 is a Receivables patch which is recommended in April 2006 Critical Patch Update. This patch can be applied on an instance where you have already applied Financials Family pack G. As an oversite, this patch was applied on an instance where Financials Family pack F was installed. As a result this patch had to be reversed. Now we all know that there is no official way to undo a patch other than restoring from backup. However in the case of this patch, we found that it had only two file which were being executed. The first file was a .sql which was creating a view. The second file was a .pls file which was creating a package body. The easiest way to reverse this patch is to run the .sql and .pls file it has kept in the patch/backup directory. However there was no .sql file in backup directory. Only the .pls file was present.
This means that the view could be dropped. We ran the .pls and it failed complaining about a procedure init which was present in the package specification but not in the package body. So we compared the versions of specification and body with a fresh 188.8.131.52 instance. The package body version in the backup directory matched with the fresh instance. So we took the package specification from the fresh 11.5.10 instance and the package and its body compiled ok. This way the patch was reversed.