[Dovecot] how to configure dovecot, Error

Hi,

we are using Squirrelmail, imapd is dovecot. OS is Debian Sarge. When I want to login with Squirrelmail the connection to the imap-server is aborted. /var/log/mail.log gives the these log-entries: Oct 25 14:39:36 webserver dovecot: imap(rs.messegrafik-schreiber.de): mbox: Can't create root IMAP folder /home/rs.messegrafik-schreiber.de/mail: Permission denied Oct 25 14:39:36 webserver dovecot: imap(rs.messegrafik-schreiber.de): MAIL environment missing and autodetection failed (home /home/rs.messegrafik-schreiber.de) Oct 25 14:39:36 webserver dovecot: imap-login: Login: user=, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured Oct 25 14:39:36 webserver dovecot: child 31339 (imap) returned error 89

Need help, thanks.

Roland