restarting window manager's time

[Al Sparks]

Fedora (and RedHat) place the time of the machine on the right hand
corner of the windows manager.

When a machine is out of sync, I'll go ahead and configure ntp to work
with our intranet's time server.

When the machine time is in sync as evidenced by invoking the 
   $ date
command, the window manager's time is still on the old time.

How do you get them in sync w/o rebooting?
  === Al