E-Mail Archiving

I've handled this in a couple of different ways. At a government site they forced everyone to delete mail after 90 days, but that may not help you. At another site, we auto-archived mail onto the users hard drive, making them responsible for keepingit clean. The downside of that was, we had to remember to copy that directory to their new PC when they got one. At another site, we auto-archived onto the server, but that ran into lots of HD space. I would go with auto-archive to the PC HD. If it fills up, the user has to figue out what they want to delete, and it doesn't effect anyone else on the network.
Hope that helps.

You may have taken the first step to most probably the simplest option with your current configuration.

Your emails are in html format.

Ever considering creating a internal website with appropriate access rights to the users so they can uploadmaterial to be archived and view it all whenever they like.

This will give you some benefits such as:

a) All mail stored in a centralised location
b) Secure (based on your permission levels) and easily accessable by users
c) Access to data can be optimised by indexing www server (faster searches)
d) Access to data can also be optimised by getting your proxy to cache the local servers contents (faster access through proxy client)

All this of course hinges on you having a www server.
hope this helps,

jb