Gaim at least uses the MIT-SCREEN-SAVER extension to do these
idle use queries. In theory, this should disable that extension;
unfortunately, I'm at work and not in a position to test this.
SubSection "extmod"
Option "omit MIT-SCREEN-SAVER"
EndSubSection
But give it a try; verify it disabled the extension by using xdpyinfo.
Of course, the downside is that you lose any screensaver applications.
:-(
--
{michael}