need help: Entourage - "rename attachment"

I am a total noob with Applescript, but realize that it could save me many headaches if I can get a handle on the syntax. Here is my issue.

I run a number of rules in Entourage 2008 (v 12.1.5) that look at each message that comes in. If the message has an attachment, it saves the message to a folder dependent on the subject line (hard coded from our website). All this works great and has been a huge time saver, but I need to tweak it a bit to get the results I require. I need a way to “rename” the attachment - basically strip some of the information from the name of the attached file.

How can I do this using Applescript? Would this be something that would replace the rule or run as a part of the rule? I noticed in the rules definition that I can have it run a script, so this is where I believe it would need to happen.

Could anyone get me started?

Thanks in advance.

Browser: Firefox 3.6.13
Operating System: Mac OS X (10.6)