Quoting duncan (duncan at sodatrain.com):
> Im looking to host a webmail system on a domain that I host.
> 
> I would like to have the ability for users to self-register via the web,
> and then log in and have a functional email acct. (ala hotmail and the
> million other webmail services.)
> 

Setup PAM to sent auth requests to LDAP.

A very simple hack to IMP and you can put accounts into LDAP and viola, you got
hotmail.
-- 
Bob Tanner <tanner at real-time.com>       | Phone : (952)943-8700
http://www.mn-linux.org                 | Fax   : (952)943-8500
Key fingerprint =  6C E9 51 4F D5 3E 4C 66 62 A9 10 E5 35 85 39 D9