Advanced Search by Event Registration Fails

Running an Advanced Search and entering an Event and clicking on Registered (and no further search parameters) appears to bring up a list of all contacts who registered for any event, not just the selected event.

Steps for recreating this:

1. Create new event
2. Register for it
3. Search for it, as above

This procedure today on the demo site brings up the wrong search results. It brings up too many records, including those who never registered for this event. As noted, it appears to bring up a list of all contacts who registered for any event, not just the selected event.