[Zope] (off-topic) Apache front-end for Outlook Web Access?

While setting up Apache rewrites to my zope vhosts, I wanted to include a rewrite to act as a front-end for my outlook web access service by rewriting the url to the appropriate localhost port, as I'd done with zope. However, while it is capable of bringing up a login screen, it gives a server/dns error. I can access it directly, though of course that's the ugly way. Anyone know how to set this up? TIA -- Keith