User registration password

Hallo, I have a problem when I use the non local smtp server,
but I wonder if somebody have maked a hack or something who makes that when users register themselves the got their username they entered in the registration form as their password so they can login to gallery directly after the registration and then change the password to that they want..

actually I need that my users can register themselves without my help and skip that e-mail gallery sends out because it don`t work for me