Autoconfiguration is helpful for not having to enter usernames and servers, and can be done using Mozilla's MCD (Mission Control Desktop).
Information is available here:
Good examples here:
NB If you don't want to lock preferences you can substitute "defaultpref" for every instance of "lockpref".
And this looks like they've used the above as a reference:
Also in there is LDAP related configuration, for example for getting a user's full name from just their current login account name. LDAP addressbooks can be configured from there also.