"You will need to install Microsoft Exchange 2003 System Manager ONLY"

Installing BES on Server 2008. I take it you install the Enterprise version of exchange tools and not the std version?
Ive selected Custom and then install - system management tools
I get the message iis snap-in component of iis is not installed. I have added the webserver iis role with the defaults. So what is the exchange sys management after?

Edit: ok just used mapi&CDO instead.