Profile front-end search not working properly with Joomla

In Joomla 1.0, when one looks at the profile "Find Contacts" form on the front-end, you notice that no matter what you enter in the search fields, the results always show all the contacts.

Interestingly enough, when you look at the details of one contact, and then you click on, say, the City for that contact, the filtering result works properly.