Here you can find daily SNAPSHOT distribution tarballs of RPM 5.1.

  A snapshot tarball is named rpm-5.1.SNAPSHOT.YYYYMMDD.tar.gz and
  consists of the latest CVS HEAD state as of "YYYY-MM-DD 23:59:59 UTC".
  
  They are NOT INTENDED FOR PRODUCTION USE, but can be used by
  distribution vendors and other interested RPM development fellows to
  test-drive RPM 5.
  
  The tarballs are the result of checking out the RPM 5 sources from
  the rpm5.org CVS repository, generating all auto-generated auxiliary
  files, running a minimal "configure" step and then rolling the
  distribution tarball with "make dist".