Problem with IMAP usernames

Problem with imap usernames I don't know if its problem of my host or its general to imap, usernames of email are a code "mXXXXXX" in server and nicks person (@domain.com http://domain.com) are apart, nobody knows its server code but their nick, and using roundcube they can only login with server code and not nick like quirrelmail (but users hate squirrelmail). I wonder someone knows how to fix this. Its installed on: http://turismointernacional.com.co/mail

If someone needs spanish translation of roundcube i did it. Email me (delreal (at) zonacronica (dot) net) -- ................................................................................. Oscar Del Real _In.pix.we.trust. // http://ipwt.zonacronica.net