if your handbrake shoes are at different extensions, the handbrake lever will still be "soft" and pull up further.. to fix this you will need to extend both handbrake shoes out by flicking little switch up ( i think up) through the hole in the rear rotor..
i assume you know how to do this.. make sure the handbrake is off when you do this and just keep checking as you adjust ie flick up 2 clicks each side (perhaps click all down so its at its lowest setting) and just keep clicking, pull up handbrake to check tension, release and adjust by more clicks if neccessary.
then once your happy leave the handbrake ON and use a wheelnut on a bare stud (no wheel) and turn the rotors each side to check the lock of the handbrake.. if the rotor makes a big movement before locking it is not engaging properly and the diff is locking with the handbrake on the other side.
i could explain it betterer but you get the jist.