'git clone bzr::lp:debian/git' dies with "No such file: 'changelog.upstream-20100406203816-j4gb4wagb3zcq42p-2000'"

Testing out the git-remote-bzr tool:

| $ git clone bzr::lp:debian/git git-test
| Cloning into 'git-test'...
| You have not informed bzr of your Launchpad ID, and you must do this to
| write to Launchpad or access private data. See "bzr help launchpad-login".
| Most recent Debian Sid version: MISSING
| Most recent Debian Sid version: MISSING
| Traceback (most recent call last):map 0/9
| File "/usr/lib/git-core/git-remote-bzr", line 49, in <module>
| helper.process(sys.stdin, sys.stdout)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/git_remote_helper.py", line 168, in process
| self.process_line(l, outf)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/git_remote_helper.py", line 184, in process_line
| self.commands[argv[0]](self, outf, argv)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/git_remote_helper.py", line 120, in cmd_list
| for ref, git_sha1 in refs.as_dict().iteritems():
| File "/usr/lib/python2.7/dist-packages/dulwich/repo.py", line 202, in as_dict
| ret[key] = self[("%s/%s" % (base, key)).strip("/")]
| File "/usr/lib/python2.7/dist-packages/dulwich/repo.py", line 273, in __getitem__
| _, sha = self._follow(name)
| File "/usr/lib/python2.7/dist-packages/dulwich/repo.py", line 255, in _follow
| contents = self.read_ref(refname)
| File "/usr/lib/python2.7/dist-packages/dulwich/repo.py", line 231, in read_ref contents = self.read_loose_ref(refname)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/refs.py", line 134, in read_loose_ref
| return self.object_store._lookup_revision_sha1(revid)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/object_store.py", line 560, in _lookup_revision_sha1
| self._update_sha_map(revid)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/object_store.py", line 368, in _update_sha_map
| self._update_sha_map_revision(revid)
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/object_store.py", line 468, in _update_sha_map_revision
| for path, obj, ie in self._revision_to_objects(rev, tree, lossy=(not self.mapping.roundtripping)):
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/object_store.py", line 422, in _revision_to_objects
| self._cache.idmap, unusual_modes, self.mapping.BZR_DUMMY_FILE):
| File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/git/object_store.py", line 234, in _tree_to_objects
| [(ie.file_id, (path, ie)) for (path, ie) in new_blobs]):
| File "/usr/lib/python2.7/dist-packages/bzrlib/revisiontree.py", line 228, in iter_files_bytes
| raise errors.NoSuchFile(e.file_id)
| bzrlib.errors.NoSuchFile: No such file: 'changelog.upstream-20100406203816-j4gb4wagb3zcq42p-2000'

Using bzr-git 0.6.6+bzr1560, Dulwich 0.8.3, git 1.7.9-rc2. Reproducible. Cloning with "bzr branch lp:debian/git" and then "git clone bzr::$(pwd)/git git-git" avoids trouble. Known problem?