one need to run before make oldconfig
d'oh! one need to add this information in the fine manual :) http://www.debian.org/doc/FAQ/ch-kernel.en.html
just look up the apt lines of aboves wiki page concerning the buildserver, you find prebuild 2.6.19 and 2.6.20-rc5 images.
$ apt-cache search 2.6.19 linux-doc-2.6.19 - Linux kernel specific documentation for version 2.6.19 linux-kbuild-2.6.19 - Kbuild infrastructure for Linux 2.6.19 linux-manual-2.6.19 - Linux kernel API manual pages for version 2.6.19 linux-patch-debian-2.6.19 - Debian patches to version 2.6.19 of the Linux kernel linux-source-2.6.19 - Linux kernel source for version 2.6.19 with Debian patches linux-support-2.6.19-1 - Support files for Linux 2.6.19 linux-tree-2.6.19 - Linux kernel source tree for building Debian kernel images $ apt-cache search 2.6.20-rc5 linux-support-2.6.20-rc5 - Support files for Linux 2.6.20-rc5 linux-tree-2.6.20 - Linux kernel source tree for building Debian kernel images Maybe image are not built for powerpc? -- Jean