The glibc-devel package depends on the kernel-headers package, which oddly enough does not appear to be included in RH 7.0, and further, the kernel-headers package conflicts with the kernel-sources package, which *is* included with RH 7.0.
The kernel-headers package *does* exist in 7.0. I'd check your tree to make sure it's complete.
The kernel-headers package for the 2.4 kernel is in Red Hat 7.0, but not the kernel-headers for the 2.2.16 kernel. Sorry that I didn't clarify. It's the latter that I'd expect to see glibc-devel depend on, considering that it's the 2.2.16 kernel that is installed by default. Maybe the kernel header files for 2.2.16 and 2.4 are interchangeable, but pardon my discomfort at the idea of installing kernel-header files for 2.4 on a system based on a 2.2.16 kernel just to satisfy the dependencies of the glibc-devel package.