My Ventrilo Banner is on this website

http://hopeless-heroes.xippy.co.uk/

When this certain individual connects to our Ventrilo server, his name is clearly "lock", it even says lock has connected and you can see his name as lock when you view the ventrilo client..

However the Gametracker Ventrilo Monitor/Banner displays his name as XXXXXXXX.

I thought it might have been a strange bug, but its been like this for over a week now and only ever does it with this same person, all the time. It just wont show his actual name on the Gametracker Banner, it displays everyone elses name just fine, except Locks.

Anyone have any idea why this is happening and how we can fix it? Only does it for this one person like I said

Thanks