Exchange not showing in iSync?


I setup my Mail client to work with a test exchange server.. It reads and sends emails fine.. The only thing I can't get to work is the sync'ing of the address book.. I setup the address book option to sync with an exchage server.. I type the address ( and i fill in the user name and password.. I click ok and then it thinks for a while and then it shows I can click configure again. I click configure and for the address it changes it to which is correct in thats where the exchange server is.. The help says I might need to go to the website manualy once with my browser.. I do that to the above link and loads up nicely.. I close safari, close address book and close mail.. I open iSync and there's option to sync to exchange manualy.. The only thing I see if the sync button and the default .Mac account icon.. Oh, just for the record I am the one setting up the exchange server.. I need to test this setup before I deploy to clients office.. I really would like to switch over some of their machines to Mac box's.. Is there something specific I should be doing on the exchange server as well?