It would be nice if the message in Maintenance mode supported some sort of code. (unless I miss typed something) I'm in the middle of move'n hosts so I've left the old forum in maintenance mode telling people where to go untill the domain is transfered.
Just curious but why is the option for maintenance mode in the edit server settings and not maintenance section?
Well, it's actually quite easy to get the maintenance mode to allow bbcode:
In Themes/default/Login.template.php
Find:
<td class="windowbg">', $context['description'], '</td>
Replace with:
<td class="windowbg">', doUBBC($context['description']), '</td>