How to get dovecot to use postfix mailbox?

I try to get postfix and dovecot up and running. I have a little problem with the mail-box path that connects both. **Postfix** virtual_mailbox_base = /var/vmail virtual_mailbox_domains = mydom.org This creates a file /var/vmail/mydom.org/sam as an mbox-file if I send to sam@mydom.org. The sent mail is inside of that file. So far - so good. But in dovecot I have this for a virtual user. sam@mydom.org:{PLAIN}mysecret:5000:5000::/var/vmail/mydom.org::userdb_mail=mbox:~/%u That creates /var/vmail/mydom.org/sam@mydom.org/inbox after successful login. So my POP3-client finds always an empty mailbox. If I copy the postfix-mailbox to the inbox-file, then POP3 gets the message. How do I get dovecot to use the postfix-mailbox or postfix to use the dovecot-file? I tried several settings in dovecot but I did not get it going to use the posfix-file as it is. Thanks!