Firefox 3.6 is supported with QTP 11, only on Windows
Chrome is not supported
Safari is not supported
Attaching the PAM. It has all the information you need to see what is supported with QTP. There are some recent patches that extend support on existing technologies. Let me know if you need additional information and will try to gather that data for you.
We just released Add-in for QTP (all versions) that lets you run your old test on any latest and major browsers (including Safari,Opera, HtmlUnit...) as well as Android and iPhone (devices and emulators)