If you enter your current password and then enter your current password again in the new password box, it seg faults. If you enter your current password and then enter a new password it does not alter your password at all.
Could not reproduce this on a non-NIS system. Were you trying to change your password on a system that is using NIS?
I'm going to assume that this particular instance was fixed, between the pwdb fixes that gafton did earlier and the recent malloc fixes in usermode-1.15, unless I hear otherwise. I definitely can no longer reproduce this or any similar problem at this time, to the best of my knowledge.