Although it's more common on T-tails, you don't necessarily need one to have a deep stall, but you do need an aft CG (e.g. F-16). Same description, though, airplaine sits relatively level or nose high and just drops like a rock. It's not an automatic death sentence, though. In the F-16 you can pitch-buck out (if you're good) and on other types, you may have enough lateral or directional control to enter a spin and recover from there.
One more interesting thing about the "coffin corner"; I've heard that the U-2 can actually get so far into it that in a turn you can actually get stall buffet on the inboard wing and Mach buffet on the outboard. Don't know if it's true or not, but it sure sounds like a scary place to be.