IE Vs Firefox problems

[Myth024]

So I noticed that IE doesn't do very will with displaying border images as well as a number of other things related to CSS. I was wondering if anyone knew how to have multiple themes based on the type of browser. I know how to do this using a normal web page and standard CSS but the phpfreechat system works differently. Thanks for the help.
<<quick update>>>
I wanted to mention that I've attempted to use PIE as well as trying to integrate some kind of detection script, but as of now I still haven't figured out the solution.

[livewiremaxx]

IE also doesnt display the whos online

[Niark]

It need to create a css file for the compatibility of IE.