help needed in discovering map bug

[nixxy]

we have already a lot of selfmade maps running sucessfuly
running on our ut99 servers but somehow the last
few makes the servers crash or if they run they use nearly 98%
of cpu-power without containing any weapons in it

the serverlog does show this error-msg:

SniperRifle DM-(bah)-LittleStation.SniperRifle14 (Function Engine.Weapon.SpawnCopy:004D) Attempt to assigned variable through None
SniperRifle DM-(bah)-LittleStation.SniperRifle14 (Function Engine.Weapon.SpawnCopy:0059) Accessed None

the whole log is filled with the same error-message

same happens to a few other maps too
they are running fine in singleplayer modus and over lan
but when we put them on the server they mostly just crah the server

anyone here who could explain me what there is going on?
im not a mapper myself just a serveradmin