kernels 2.2 and below doesn't have pentium 4 support ,but it doesn't essentially mean that redhat won't install.only thing is that
u won't get the pentium 4 output that u desire..
u should get a kernel 2.4 or higher from kernel.org and compile it for pentium 4 support..
i have redhat7.0 with 2.2 kernel which doesn't support pentium 4
so i downloaded and complied kernel2.4 ... that works.........
go thru /proc/cpuinfo for knowing how linux has identified ur processor........