Primary email address woes

[Gerald Brandt]

Hi,

When I type in a users name in Webmail, it shows the users primary email 
address.  In our case, because we are moving from an existing system, 
the primary email address is not the REAL email address. The one that 
gets sent out to the world.

There's gotta be a way to change this.  I was just about ready to go 
live.  Can it somehow use the requested identity of the user, as set in 
preferences?

IMAP and SMTP login are also a PITA, though only at setup.  The web page 
will let the user login with gbr, even if their primary email is 
gerald.brandt.  But Postfix and Cyrus insist on primary_email at full.domain

Gerald