Whatever the solution, I support getting some sort of weapon to fight griefers up and available on the ZM server - it's becoming harder and harder to spend an evening on the game without encountering some kid thinking it's funny to prevent map completion by blocking doorways or hiding objective items. ZM is all about coop, which means it's also very easy to ruin the game if so you want.
At the very least, it would be very nice to have some sort of votekick/voteban option, which would at least ban the target for half an hour or so (just kicking means the griefer would be back next round - on ZM I've seen plenty of them not getting discouraged by a simple kick/slay).
The other advantage of votekick/voteban is that it would allow people to deal with griefers themselves - there are already not many people playing ZM, so it'd be hard to have an admin available all the time.
Otherwise, it'd be nice to have some IRC channel or the like to be able to call an admin in in case there's a griefer currently active on the server.
In any case, I'll now start gathering Demo files of griefers, as I've just discovered this handy topic [
http://www.conjointgaming.com/forum/index.php?topic=9970.0 ]. It won't help as an "immediate reaction tool", but at least we can hope to prevent those griefers from joining the server later on.
Thanks in advance for the help!