[Dovecot] IMAP login name conversion

Hi all,

Out IMAP client (Outlook and others) use login name like joedirt@domainname.com

I need dovecot to convert it to joedirt-domainname_com since that is the local login name. Can someone give me a hint how to do that? Is there any simple way to do it or do I have to modify any source code?

Thanks, Zoong