This was already very discussed but seems not to have consensus and therefore I insist.
The passwords are defined by the administrator of the system and not by the user. Maybe y ou can put an option to use clear passwords or incripted. In the option of clear passwords these would be attributed automatically by the system. So there would not be the problem of knowing common passwords of the user. This waywe solve the problem of a client that have configured several programs, for example for access to a ftp area, and don't remember the password and would have to reconfigure all the programs. Perhaps you can also separate the ftp passwords of the email passwords … This will help a lot.