Install the Portable Firefox 3.6.x version on your hard drive for accessing that website. It won't affect the current version you have installed.
http://portableapps.com/apps/internet/firefox_portable/localization#legacy36

Many thanks.

You're welcome.

Please click the Solved It button next to the answer that answered or solved your Firefox support issue, it appears when you are logged in, so this thread gets marked as Solved to help other users who may have this same problem.