I have been having a similar problem with my 2.6.10 kernel. My wife decided she just HAD to have an Epson CX4600 MFD (printer/copier/scanner), and CUPS and SANE were both convinced that it was a cleverly disguised paperweight. Apparently I offended KDE when I upgraded SANE and CUPS, and suddenly I was receiving an error message saying kdeinit could not be started, and that I should check my [KDE] installation.
Long story short; I put in CD2, cd'd into cdrom/slackware/kde, fired up pkgtool and reinstalled that badboy. Seems to have done the trick, I'll find out when I boot up in the morning (my slackbox is currently located in our bedroom, and the fan keeps my wife up, so the system gets halted every night
Hope it works!
--Well, I was partially successful. KDE starts up, but I've killed the sound somehow.