Why does this happen?

I just installed perlfect search 3.31 on our intranet. Install went fine,
index was fine, everything seemed ok.
 
And my initial search for a word returned results ok. The problem occurred
when i attempted additional searches from the original search screen (not
from the results screen).
 
If I go back to my search screen and type in a different word to search, the
result screen returns results from my previous search. I have to "refresh"
the screen manually to see my new search results. It does this consistently,
even if I close my browser, clear my history, and start over with a new
browser instance.
 
Any ideas why this occurs?
 
Thanks,

Brian