[imp] help with config

[Jeff]

I just installed the framework and several modules from cvs on FreeBSD 
6.x.  I could really use some direction getting the login configured. 
I chose imp for authentication and that works fine. I'd like to use 
dimp, but choosing that option from the horde menu doesn't work.
I assume this is because dimp only sits on top of imp.

Do I need I hook for this? I've googled until I'm blue in the face and I 
don't find an answer. There is no login.php for dimp and I assume that's 
as it should be (dimp works fine once you're logged in.)
Any help or direction would be greatly appreciated.