It's a Private (Corporate) Site, connected to SAP (BW) it works perfectly with Firefox 3.6.5
Error: Sorry, your browser/program is not supported by Web Dynpro! (With IE 8 this problem is solved with Compatibility View!!)
Not sure if this will work for everyone, but it worked for me. I installed User Agent Switcher add-on (https://addons.mozilla.org/en-US/firefox/addon/user-agent-switcher/). I then added my own User Agent with the following string in the "User Agent" field:
Mozilla/5.0 (X11; U; Linux x86_64; de; rv:220.127.116.11) Gecko/20100723 Ubuntu/10.04 (lucid) Firefox/3.6.8
I also set "App Code Name:" to "Mozilla" (less quotes) and "App Name:" to "Netscape" (less quotes)
all other fields I left empty
Hopefully this works for you...