Fix Template

I have an old Jooma 1.0 website that has been working just fine but recently stopped rendering correctly in Firefox, Chrome & Opera. It works fine in Internet Explorer. [login to view URL] In the past this has happened if an image was too large in the center main content area (the main content area & left columns get pushed down below the right column) but that is not the case anymore. No changes have been made recently to the website but the main content & right column is being pushed down the page. I have tried using Firebug to debug the problem but can't fix it. It seems like it is a simple CSS adjustment that should not take more than 1 or 2 hours to diagnose.