[imp] IMP 3.1 / user@domain.ext on virtual domains

[Amith Varghese]

> Isn't the above the result what you would get just by logging in as
> user@foo.bar and having realm=kabissa.org?

for the most part, but they don't really need the @kabissa.org.  The realm needs
to be set to whatever the user entered with their login.  But the problem exists
because the user is now considered user@foo.com when all Tobias wanted was
"user".  I think my previous solution might work, but its a little wacky.

Amith