Firefox does support 128 bit encryption, so you can ignore that warning on the browser check page.

• http://www.opm.gov/e-QIP/browser-check.asp

If websites complain about 128 bit encryption not available then that can be caused by the "U;" that is no longer present in the Firefox user agent.

• http://en.wikipedia.org/wiki/User_agent#Encryption_strength_notations

Firefox supports 256 bit encryption ciphers since Firefox 2 was released in 2002.

• https://www.fortify.net/sslcheck.html

We did not detect that your web browser supports 128-bit high encryption. If you have trouble connecting after you click the "Continue" button below, you will need to upgrade your web browser to a version that supports 128-bit encryption.

This is the message I get when I try to log on to this site so who ever is saying Fire Fox supports 128 bit encryption please explain this message

Firefox does support 128 bit encryption and even 256 bit if site provides the support.

The problem is the http://www.opm.gov is outdated in their browser sniffing in looking for the U in useragent as that was more applicable say ten+ years ago then now. The U was removed as of Firefox 4.0 release. The details about the U is in the second link posted above.

I even contacted them about this some months ago and email even got forwarded to somebody to deal with this but neither got back to me since.

For this one site you could either use the portable Firefox 3.6.22 (will not impact you Firefox 6.0.2 install) or use useragent switcher extension on 6.0.2 to change to a earlier Firefox version like 3.6.* to fool the website.

http://portableapps.com/apps/internet/firefox_portable/localization#legacy36
https://addons.mozilla.org/en-US/firefox/addon/user-agent-switcher/

Thank you very much