It's so silly, but very funny indeed (see also the comments on Schneier's post).
But I guess it's only possible because this particular bank really messed up, isn't it? Custom security questions are meant to be used in netbanking, not to be asked by humans.
This is excellent! I wish more systems would let you configure the secret question instead of giving a set of predefined questions... (eg. mother's maiden name, first school, first friend, first town, etc), and most of those questions can be found out about a person with some small talk. For places like that my solution has been to give scrambled answers (eg. city of birth, the answer 'colombo' becomes 'obmoloc'. Also this isn't my scrambling method or answer, just an example).
Another simple but effective hack: have a standard untrue answer for your mother's maiden name, first school, etc. Only you will know them. Your mother's maiden name is McLuvin.
I usually provide an untrue date of birth to places where it doesn't matter. The only places that really need to know are the places that also need your SSN. Everybody else just likes having sensitive info lying around.