There is now a Quake 3 Arena mod named Q3 Fortress. It is a newly-coded mod, designed from the ground up for Quake 3, which attempts to recreate as faithfully as possible the gameplay of Team Fortress. Not to be confused with Team Fortress Classic, which is based on the Half-Life engine.

The Q3F mod is a worthy mod, but it doesn't retain the gestalt of the original Team Fortress. Something about the play balance in the original made it sheer magic; the character classes' weapons were balanced well, as were their abilities. QWTF running the 2fort5 map was probably (IMHO) the best multiplayer shooter game of all time, and has not yet been surpassed. Quake 3 Arena, while much prettier and with nice tricks that make it a cool game all by itself, is too much of a technology show and not enough of a gameplay experience.