I've just remembered (after a very campy round on casa) that there once where such features for public CS servers (dunno if it still exists). I don't know if it's at all possible with urbanterror, but I think this is nice for public servers.
What does it do? After a certain time (say 5-10 seconds) on the same spot you get a big text warning (sth like Don't just sit and wait morron), few seconds later (1-3) if the player still is at the same spot he get's a slap (if possible one moving him a few meters into the front; damage from 20-50% would be nice too ), maybe a warning would be good too.
I realise that this might become a problem while bandaging, but doing a few steps in the meanwhile shouldn't be a big problem.