Hello Giora.

Hopefully this support article is what you need:

http://support.mozilla.com/en-US/kb/Upgrading+to+Firefox+3.6#Upgrading_from_Firefox_2_or_earlier

Hello Morbus

Thank you for your answer. I found this : "The installation file provided by Mozilla in .tar.bz2 format does not contain sources but pre-compiled binary files, therefore you can simply unpack and run them". That is my situation, but my problem is that I don't know how to run it. I've executed the shell script "Firefox", once, and I've got the new version, but after I closed it, I could not start Firefox with the icon, it was again the old version, so I've uninstalled everything to start again from the beginning, and now it's not working at all, nothing happen if I run the shell script.