Nobody here answered my question about using kernel-patch .deb files, so I'm going to answer myself. This way, anybody searching the list archives will at least gain a little info and maybe get over this hump more quickly than me. I have had a separate email exchange with Manoj Srivastava, the author of the kernel-package docs, that got me through my difficulties.
If you have compiled a kernel before installing the patch package, it is likely you will have no problem. The difficulty seems to arise if, like me, you install the kernel-source package and immediately install the kernel-patch package. You need to then either set an ENV variable or add a line to /etc/kernel-pkg.conf: patch_the_kernel := YES. At that point you should be able to do something like: make-kpkg --config xconfig --revision=3:1.epting-idedma.1 kernel_image However, in my case this failed because I lacked an existing .config file in /usr/src/kernel-source-2.2..17. My simple-minded solution was to do a make-kpkg clean, then xconfig, change a few things, save and exit. Then the big command above correctly applied the patch, executed make xconfig (allowing me to set up the new options provided by the ide patches) and then proceeded correctly to make a kernel-image .deb. And now I have udma working with my ASUS P5A/ALi 1541 chipset.