Firefox 4, unlike Firefox 3 or chrome, is 64 bit application, and MultiClutch works only with 32 bit ones. Here's an update of MultiClutch's inputmanager to 64 bit: http://blog.prashantv.com/2009/minor-multitclutch-update/

Remember to remove /Library/InputManagers/MultiClutchInputManager though, or you may experience some problems

Some gestures have been removed in Firefox 4.
You can restore the zoom feature by changing the values of the related prefs on the about:config page.

browser.gesture.pinch.in cmd_fullZoomReduce
browser.gesture.pinch.in.shift cmd_fullZoomReset
browser.gesture.pinch.out cmd_fullZoomEnlarge
browser.gesture.pinch.out.shift cmd_fullZoomReset

• http://kb.mozillazine.org/about%3Aconfig

Got it. Thanks.

cor-el

Do you know why the multitouch has been disabled ?

Best regards

Not using multiclutch. Using multitouch, like on the newer macbooks, etc.