Three strange problems arised from - I don't know from where to be honest...
This is what happens:
- When a new maildomain is created nothing happens until a new mailuser is inserted (intended behavior as far as I know). When a new mailuser is created the following problems arise:
1. The maildomain.name [f.e. test.int] has the permission-set 0755 (owned by vmail) and not 0700 - is that intended behavior?
2. The maildir of the new mailuser is owned by the user root (0700) which obviously leads to trouble during maildelivery.
3. If the mailuser is updated (function user_update in mail_plugin.inc.php) the user is honored by applying the correct owner to his maildir.
I thought that my problem would reside in the mail_plugin.inc.php and I compared it with the "install-version" and only found the changes that I applied - see here
I've attached my mail_plugin.inc.php as textfile - maybe someone can give me a hint what's going wrong here. (It seems that line 123 is not executed. All changes are marked with "osterhase".)