Cloning channel using spacewalk-clone-by-date ends with deadlock error

Issue

When cloning a channel using spacewalk-clone-by-date a deadlock error is hit:

Traceback (most recent call last):
  File "/usr/bin/spacewalk-clone-by-date", line 251, in <module>
    sys.exit(abs(main() or 0))
  File "/usr/bin/spacewalk-clone-by-date", line 241, in main
    return cloneByDate.main(args)
  File "/usr/share/rhn/utils/cloneByDate.py", line 191, in main
    cloner.clone(options.skip_depsolve)
  File "/usr/share/rhn/utils/cloneByDate.py", line 356, in clone
    self.dep_solve([pkg['nvrea'] for pkg in added_pkgs])
  File "/usr/share/rhn/utils/cloneByDate.py", line 379, in dep_solve
    self.process_deps(dep_results)
  File "/usr/share/rhn/utils/cloneByDate.py", line 418, in process_deps
    cloner.process_deps(needed)
  File "/usr/share/rhn/utils/cloneByDate.py", line 500, in process_deps
    self.remote_api.add_packages(self.to_label, needed_ids)
  File "/usr/share/rhn/utils/cloneByDate.py", line 689, in add_packages
    self.client.channel.software.addPackages(self.auth_token, label, pkg_set)
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1199, in __call__
    return self.__send(self.__name, args)
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1489, in __request
    verbose=self.__verbose
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1253, in request
    return self._parse_response(h.getfile(), sock)
  File "/usr/lib64/python2.6/xmlrpclib.py", line 1392, in _parse_response
    return u.close()
  File "/usr/lib64/python2.6/xmlrpclib.py", line 838, in close
    raise Fault(**self._stack[0])
xmlrpclib.Fault: <Fault -1: 'redstone.xmlrpc.XmlRpcFault: unhandled internal exception: ERROR: deadlock detected\n  Detail: Process 32200 waits for ShareLock on transaction 3041893; blocked by process 32068.\nProcess 32068 waits for ExclusiveLock on tuple (6,24) of relation 17242 of database 16384; blocked by process 32200.\n  Hint: See server log for query details.\n  Where: SQL statement "update rhnChannel set last_modified =  $1  where id =  $2 "\nPL/pgSQL function "update_channel" line 23 at SQL statement'>