I don't know how to ban but to kick ppl off your server type in the console:
kick <playername>
I think to ban you would have to have a bannned.log file somewhere and figure out some way of invoking it.
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3rd Battalion
504th Parachute Infantry Regiment
82nd Airborne Division
"The Blue Devils"
[This message has been edited by 3/504th-Cpt.Knight (edited January 04, 2002).]