[1.33]SMP Minecraft 1.2.5 Tekkit 1.3.2

I am having a problem with people editing the computers at my servers spawn region. The region is protected from building and destroying with world guard, and the computers themselves are behind walls but someone on the server manages to use the computer from behind the wall and edit the program which displays things onto a monitor.

How does he manage this, and how can I protect the computers from being used at spawn?

Thank you

Bukkit protection plugins have a delay in which the client thinks the block is broken - unavoidable right now. Once the block is broken there is a split second delay where someone could right click the computer.

Best way to fix is to make the program not able to be terminated.

And how would you do that