I need to force a refresh of a frame from another frame

Hey all,

I've got this test that I've doing in ColdFusion with a frameset.  2 frames....the top holds the clock and the bottom holds the questions.  Well, once the student starts the test, I'm setting the session variable to 0 which means that the clock is to run.  If the variable is 1, then the clock is to stop.  The clock doesn't stop running until the student finishes the test or till the time expires.  

I've got the part finished if the time runs out on the student...but if they finish with time remaining on the clock, I want to stop the clock from counting.  Since it is in the top frame, I am unable to determine how I might refresh the top frame so that it can see that the session variable has changed from a 0 to a 1.  

Student Starts Test
       - Session.Auth.StopTimer is 0
       - Timer starts at 15 minutes and counts down
Student Finishes Test
       - Student is sent to a review page to see their work, Session.Auth.StopTimer is 1
       - Timer stops counting down.

All I need if an idea of how to refresh that top frame from the bottom frame from within the set.

Thanks a lot,
Inverted_2000