Chat Pod - Private chat user list 'clipping'

I have a user (the meeting Host) running a meeting with about 10 people. When he tries to invoke private chat with users, the drop-down with the user list appears to be 'clipped' and therefore not showing all the users. I have attached a link to a screenshot. I have never seen this phenomenon before.

Note how the last user on the attendee list is not appearing on the private chat drop-down (even though the scroll bar is being lowered as much as possible).