FYI, db_Main doesn't work all that well at the moment. The reason is that unless you pass it an Ima::DBI handle (not vanilla DBI) it will have problems with transactions and with automatic setup classes like Class::DBI::mysql. I think Tony posted a code snippet to the mailing list showing how to open an Ima::DBI handle yourself and pass it through to Class::DBI, which is what you should do if you can't use the set_db method.