Replacing PM system with internal email...
 

Explanation: "Internal email" refers to an excellent PHP script called b1g Mail 5 which I use but want integrated into vBulletin. The software is now under paid licscense but I have the b1g 5 files that were released under the GNU/GPL and can email them to anyone interested. The whole point of the script is to allow virtual email boxes using PHP and MySQL. Uses one POP3 with a catchall like HiveMail (which I am too cheap to buy after spending $160 on vBulletin). Except I want the email to also function as a PM system.
So we would have:
Email to a virtual address -> b1g Mail -> shows up in PM box
or
Email to a virtual address -> b1g Mail -> shows up on mail system login
http://ca.armada2files.com/nukemail - mail thing
If you want to help but are confused (can't blame you) just ask for clarification...