Map realm to user

[Pedro Silva]

Hi,
I have a postfix/cyrus/sasl mail server authenticating against an ldap 
server.

It all works fine using a 'login:password' authentication but I would 
also like to user 'login at realm:password' authentication for the mail 
accounts (imap and pop3).

The authentication bit work fine when I use 'login at realm' (in imap) but 
no mailbox is opened...
Well my question is: is it possible to map 'login' and 'login at realm' to 
the same mailbox? and if so how can I do that?

Thanks
Pedro Silva
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