FireFox problem

Unitl today, my pages displayed OK in both IE and FF. Now my site looks OK in
IE but in FF it shows the main content body overlapping the 'right menu'. Not
on all pages but on these particular ones,
http://www.atishameditation.co.uk/index.html,
http://www.atishameditation.co.uk/cl...ocal_area.html,
http://www.atishameditation.co.uk/webiste_sitemap.html there could be others.

What's happened to FF? Have they updated various bits? that's now coflicting
with our site?

I would be interested in finding the answer, FF has been very consistent utill
today, thought I could rely on them?

Pakman