Which unix are you wanting to do this on? I Think AIX works with WINE...
Alternatively, take a look at Evolution for Gnome. Gnome is available on most unix'es.
http://en.wikipedia.org/wiki/Novell_Evolution
Another option is to use the web front end for MS exchange, you can connect to the exchange server via https in your web browser and get a very outlook-like interface to your mail.