Hi,
this is the patches we're applying in Ark Linux - some are generally useful.

rpm-arkvendor.patch
	Recognizes Ark Linux and sets RPMCANONVENDOR accordingly

rpm-bs-implies-nodeps.patch
	Makes rpm -bs imply --nodeps -- Rationale: To generate the src.rpm only
	(e.g. to run the actual build process on another machine), the libraries etc.
	in BuildRequires aren't needed, so it shouldn't error out.

rpm-create-pentiumdirs.patch
	Create pkgsrcdir/RPMS/pentium{3,4} on x86

rpm-multiple-filesFiles.patch
	Allow for multiple %files -f files - usage example:
	%find_lang whatever
	%find_lang anotherIncludedApp
	find $RPM_BUILD_ROOT%_datadir |sed -e "s,^$RPM_BUILD_ROOT,," >dataFiles
	%files -f whatever.lang,anotherIncludedApp.lang,dataFiles

	Granted, you could also just cat the files together and use -f the result,
	but I think allowing several files makes the spec files more readable

rpm-DB_PRIVATE.patch
	We've run into db locking problems that fixed themselves with
	rpm /var/lib/rpm/__db* so often that we've decided to just get rid of the
	__db* files (by using the DB_PRIVATE flag). Not sure if this is the right
	fix, but it's a working workaround and so far we haven't seen any drawbacks.

rpm-perl-requires.patch
	Filters out perl(the) and perl(this) requirements

rpm-optional.patch
	Adds a "%optional" flag to a file -- that causes the file to be packaged if
	it is there, but not to error out if it isn't there.
	We're using this e.g. in the context of packaging arch specific headers in
	the gcc package (we prefer %optional xmmintrin.h over %ifarch %ix86
	xmmintrin.h %endif in that context because the former does the right thing
	on any new arch that has xmm intrinsics as well, without having to
	explicitly support it).

We used to apply some more patches to rpm versions from rpm.org that seem to 
be obsolete in rpm5.org - such as making sure a pentium3 package can be 
installed on pentium4 and athlon (compatible, just not optimal). This touched 
the CPU detection stuff in lib/rpmrc.c, which isn't there anymore in rpm5 - 
if the patch is still needed (haven't checked yet), it'll need to be redone.