Force password change cannot be unchecked once selected

To reproduce the Bug:

1. as admin, access a user's profile
2. check the "Force password change" checkbox and save changes
3. quit the user's profile page
4. access again the above user's profile page, and now deselect the "Force password change" checkbox
5. save profile changes
6. quit the user's profile page
7. re-enter the user's profile page
8. the checkbox "Force password change" is still selected