I did it with RH5.1 no prob at all (Score 1)

I upgraded to 2.2.0 (and 2.2.1 since) on 2 seperate RH 5.1 machines with 0 problems. It was just like tracking kernel releases always was with either 2.x tree; download kerenl, remove linux symlink, untar in /usr/src, rename to linux-2.x.x, symlink linux over to it, then the standard makes (menuconfig,depend,zImage,modules,install,modules_ install) and away I went.

I don't see where RH5.2 is any different, it's based on the same glibc and (incremental releases aside) same compilers. It seems very strange that 5.2 would give problems where 5.1 didn't...