Profile field bug in 3.8.3?
 

I made a security question for the profile field to prevent spammers from login in automatically.

These fields are used:
Field Required - No, but display at registration
and
Field Editable by User - Only at registration

This is also visible at the screenshot I attached.
Attachment 30182

Now this is the problem. Older users, which did register before I made this, do not have the security question answered in their profile.
When they edit their profile, and want to save it, they get the message they did not filled in the field with the correct value.
Quote:
You did not enter the correct format for the Securitycheck! field. Please read the field description for the expected format.
AND they CAN answer the question.

Both things should not be the case, because it should only be displayed at registration and should only be editable at registration.

Is this a bug or am I missing something?

Attached Images http://www.vbulletin.com/forum/images/attach/png.gif profile.png‎ (15.2 KB)