Redhat doesn't have a sparc version of RH and the UltraPenguin distribution is very outdated. If it's a sparc architecture, then I'd recommend just putting Solaris 10 and use it's dhcp server. If you dont' like solaris' version, then grab the source from isc.net and compile that version.
If the blade is Opteron based, then you can run just about any version of Linux you like.