When you change a password of a user in the console (for 1.2.8 only), the selected security question gets deleted. Steps to reproduce:
1) Log onto console as "admin" and create a new security question.
2) Create a new user, selecting the security question + giving an answer.
3) Now edit the user again. You'll see the security question selected, and a greyed out textfield for the security answer.
4) Edit some attribute and save the user.
5) Now edit the user again...the security question has disappeared...