Description of problem: In case of touchpads the synaptics driver is automatically added to xorg.conf which is generated by pyxf86config. However, the section about the synaptics drivers is missing the option Option "SHMConfig" "on" Without this option the touchpad cannot easily be de/activated on the fly by other applications (synclient, ksynaptics).
Since this bugzilla report was filed, there have been several major updates, which may have resolved this issue. Users who have experienced this problem are encouraged to upgrade their system to the latest version of their distribution available. Please, if you experience this problem on the up-to-date system, let us now in the comment for this bug, or whether the upgraded system works for you. If you won't be able to reply in one month, I will have to close this bug as INSUFFICIENT_DATA. Thank you.
The bug is of course still valid - only Fedora 8 will show if it has been resolved.
My understanding from conversations with X people is that the SHMconfig thing is a terrible hack and a possible security risk.
SHMconfig is required to be able to turn on or off the touch pad. So as a result it is a security risk in Linux to be able to turn off the touch pad. Strange and not very userfriendly.
Bug closed as WONTFIX. For the archive: changing the touchpad behaviour is a security risk as long as every user can do this without any kind of authentication (which is the case with that option).