The public updates/[45]/ppc/debug/ directories do not contain any kernel-debuginfo-*.ppc64.rpm files. updates[45]/ppc/ contain both kernel-*.ppc.rpm and kernel-*.ppc64.rpm. There should be a general sanity check that the set pushed contains a debuginfo rpm matching each individual rpm in the main dir. Because these rpms are not available, it's not really possible for Fedora users to use systemtap with standard Fedora update kernels. The ppc64 debuginfo is included in the original dist composes.
Fixed. I re-pushed the latest FC4/5 kernels to get kernel-debuginfo-2.6.16-1.2111_FC5.ppc64 and kernel-debuginfo-2.6.16-1.2108_FC4.ppc64. I'm going to be re-writing the push process at some point in the near future, and I'll make sure to verify that each package has a corresponding debuginfo package. Thanks!