Ok you guys, I have just discovered a minor error caused by this hack, hopefully one of you can tell me what I did wrong.

When you try to delete a pm this is what it comes up with:
FYI
Invalid input! One or more items submitted in the form are not in the proper format.
ยป Please use your browser's back button to return.
You can still enter the pm and delete it from there though.
TIA, kennyp