Well, I upgraded my kernel to the latest RH 7.2 RPMs, X likewise, downloaded and installed the 1.1.20t Savage S3 driver, and added an 'Option "NoAccel"' line to my XF86Config-4 file, and my laptop has managed to stay up without hanging now for almost 72 hours. Fingers crossed..
Even with the hardware problems I've been having I still have two systems that have been up since the last millenium. :-)
Brian Behlendorf pointed out another no-op situation for autoresponder: it shouldn't bother trying to do anything if there's no address to which a reply can be sent.. Updated to 1.15.2, but no release announcement made yet.
Last week I went to add Spackle to Freshmeat, and found that Jeremy Weatherford had created a project there with the same name a couple of weeks ago. We worked it out; he changed his project's name to 'SpackleStats', and we each reference the other's project on our various pages.