"cpio: MD5 sum mismatch" error when submitting a F11 SRPM to Mock

Today I had to migrate a customer CVS repository to Subversion. I looked after cvs2svn but I only found it (at least a 'working' version) in Rawhide. "No problem ! , I'll use my mock wrapper script on my build system" ... Except that instead of building a nice ready-to-go rpm, I ended with that error message :

warning: /builddir/build/originals/cvs2svn-2.2.0-2.fc11.src.rpm: Header V3 RSA/SHA256 signature: NOKEY, key ID d22e77f2
cvs2svn                     ##################################################
error: unpacking of archive failed on file /builddir/build/SOURCES/cvs2svn-2.2.0.tar.gz;4a2d65a4: cpio: MD5 sum mismatch
Error installing srpm: cvs2svn-2.2.0-2.fc11.src.rpm

Hmm, that famous problem Russ reported some time ago .  But instead of setting up a F11/Rawhide domU somewhere just to extract the sources/spec from the rawhide srpm , I just decided to modify my wrapper script around mock on my CentOS 5 builder. Instead of just downloading the SRPM and directly submit it to mock, I first install it with the --nomd5 rpm parameter (using rpm2cpio is also an alternative), and then recreate directly a SRPM with `rpmbuild -bs --nodeps` (with of course the correct --define ' ' values for my build system) and then submit the resulting srpm to mock. I'll check later if it's possible to find a rpmmacro that can be used directly in the mock config file to bypass the srpm explode/recreate step. More informations about that issue in the Red Hat bugzilla and also on the Fedora wiki ...