Scroll Bar Synchronization - Can it be done?

Example :

I have a header in a top frame and a plot in the bottom frame. They are 1500pixels wide. At present if someone scrolls the plot it doesn't line up with the header which has to be manually scrolled to match. Is there a script which would perform identical scrolling on them both if only one of them was scrolled.

Do I need Java or something?

Thanks

Paul