MUTE KICK BAN
Works well for persistantly abusive players.
Personally I'm not at all offended when people swear; it doesn't feel inappropriate in a game of this nature. What does irritate me is when people delberatly slag others off for no good reason, make racist/religionist comments, etc. I only have a problem with abusive language (with or without swearing) that's just for causing insult and grief.
Stuff like this is just part of the game:
n00b couldn't escape l33t's grenade
joinedl8 couldn't escape l33t's grenade
uberdretch couldn't escape l33t's grenade
Taiyo.uk couldn't escape l33t's grenade
[A]n00b: Bastard!
[A]joinedl8: MY FUCKING EVOS YOU TARD
[A]Taiyo.uk: I say, spiffing grenade old chap!
As for people concerned about children being exposed to foul language in trem, I'd be more concerned about exposure to the guns and violence. What age rating would trem have if it were a commercial game?