So inlight of RU5 I thought I would share this with you. So we know the issue with the .net framework and the Certicate Revokation List.
This script updates the Exchange 2007 .config files inline with 944752: Exchange Server 2007 managed code services do not start after you install an update rollup for Exchange Server 2007
It will add the following in to all .config files (except web.config). It will also backup the original file before update
REMEMBER test in the lab before production