Horde: Login with truncated Username possible

[Johannes Graumann]

Hi,

Just realized, that when using "my.user" as the username for the horde login 
of user "my.user at mydomain.org", horde will let me log in, but will not give 
me access to "my.user at mydomain.org"'s mailboxes - there's just an empty 
setup. 
This is confusing - either prevent the login or have it lead to the proper 
mailbox ...

Cheers, Joh