Capping players rate of turn in Source

[ChromeAngel]

I've got several playable classes in my mod, I would like to distinguish them better by capping the rate at which they can turn (eg a "heavier" class is slower to tun, "lighter" ones turn faster).

Any idea how to do this, irrespective of how far the player moves his mouse or how high his mouse sensitivity is ?

It's been months since I last looked at the problem myself, but i've just been reminded by a play tester.