Update to 3.0.5.4p2 broke Shell Users

A recent update to 3.0.5.4p2 on all our ISPConfig servers in a multi-server environment appears to have broken creating and updating shell users.

When creating shell users, I get message:

Code:

08.08.2014-13:41 - WARNING - Shell user must not be root or in group root. 

After some investigation, this error is returned from within function is_allowed_user(), in file: /usr/local/ispconfig/server/lib/classes/system.inc.php

And the following line was causing the problem:

Code:

if(preg_match('/^[a-zA-Z0-9\.\-]{1,32}$/', $username) == false) return false;

Because in our ISPConfig setup, we have the Shell user prefix set to:

Code:

ssh[CLIENTID]_

(and our other prefixes also have underscores)

So shell users are created like: ssh1234_bob

The preg_match code above does not allow underscores, so now if we try to create a new SSH user on any server, or update any existing user, we get an error.

Adding an underscore to the preg_match pattern solved the issue:

Code:

if(preg_match('/^[a-zA-Z0-9\.\-_]{1,32}$/', $username) == false) return false;

Although now we have to make this manual fix across all our ISPConfig servers (over 20 servers).

Can this please be updated for the next release?
Thanks