[jQuery] Splitter plugin not responding to window resize in IE7

I'm using Dave Methvin's excellent splitter plugin to provide a 3-pane
splitter. (http://methvin.com/splitter)
Works a treat except that it does not respond to a window resize in
IE7. Other browsers are ok, even IE6!
I've experimented with the anchorToWindow and resizeToWidth options
but they did not help.
Has anyone else had these symptoms?
Many thanks,
George