The mime-procs were deleted a few years ago! So, you are chasing fixes, which are for actual versions completely irrelevant.
You should communicate your client that the policy "upgrade nothing if possible" is most likely more expensive than going to an more recent version, since you have to dig into all the changes that happened during the last 10 years in aolserver and openacs and you have to think about whether these changes are required for the client or not....
