Comment 37 for bug 54191

Yes, my second post corrects the first. The fact that you're getting the problem at all (I presume you're using Maverick?) pretty much confirms Jakob Unterwurzacher's post of 2010-09-14 for the case of Maverick, so we now know that "fix committed" is still the correct status. What I don't fully understand is by what mechanism the importance was changed from "Low" to "Unknown".

Also, that option in your xorg.conf should prevent the problem from occurring at all, no matter what X version you're using, so something doesn't make sense here. I think you *might* have used incorrect syntax in your xorg.conf, where the correct syntax would be (note not only the section but also "off" instead of "no"):

Section "InputClass"
        Option "Emulate3Buttons" "off"
EndSection