[imp] Default Identity always has example.com

[Shane Liesegang]

This is a new installation of Horde 3.0.5 and IMP H3 4.0.3.                     
                                                                                
Despite changing every maildomain and realm in servers.php, when a new          
mail is sent, it always comes up as <username>@example.com. As far as I         
can tell, "example.com" appears nowhere in my configuration. Is there           
something I've missed? Should I start digging in the database for some          
stuck option?                                                                   
                                                                                
I'm fairly handy with PHP, but am not even sure where to start looking. I       
would appreciate any help.                                                      
                                                                                
        - SJML