test_postgresql_opportunistically fails on RHEL

Using the latest version of Glance grizzly I'm seeing the following when running unit tests on RHEL (with postgres):

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ERROR: glance.tests.unit.test_migrations.TestMigrations.test_postgresql_opportunistically
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_StringException: Traceback (most recent call last):
  File "/home/dprince/glance/glance/tests/unit/test_migrations.py", line 292, in test_postgresql_opportunistically
    self._walk_versions(engine, False, False)
  File "/home/dprince/glance/glance/tests/unit/test_migrations.py", line 319, in _walk_versions
    self._migrate_up(engine, version, with_data=True)
  File "/home/dprince/glance/glance/tests/unit/test_migrations.py", line 359, in _migrate_up
    version)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/versioning/api.py", line 186, in upgrade
    return _migrate(url, repository, version, upgrade=True, err=err, **opts)
  File "<string>", line 2, in _migrate
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/versioning/util/__init__.py", line 159, in with_engine
    return f(*a, **kw)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/versioning/api.py", line 366, in _migrate
    schema.runchange(ver, change, changeset.step)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/versioning/schema.py", line 91, in runchange
    change.run(self.engine, step)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/versioning/script/py.py", line 145, in run
    script_func(engine)
  File "/home/dprince/glance/glance/db/sqlalchemy/migrate_repo/versions/022_image_member_index.py", line 33, in upgrade
    table=image_members).drop()
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/changeset/constraint.py", line 59, in drop
    self.__do_imports('constraintdropper', *a, **kw)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/changeset/constraint.py", line 32, in __do_imports
    run_single_visitor(engine, visitorcallable, self, *a, **kw)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/changeset/databases/visitor.py", line 75, in run_single_visitor
    fn(element, **kwargs)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/changeset/ansisql.py", line 272, in visit_migrate_unique_constraint
    self._visit_constraint(*p, **k)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/changeset/ansisql.py", line 284, in _visit_constraint
    self.execute()
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/migrate/changeset/ansisql.py", line 42, in execute
    return self.connection.execute(self.buffer.getvalue())
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1449, in execute
    params)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1628, in _execute_text
    statement, parameters
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1698, in _execute_context
    context)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1691, in _execute_context
    context)
  File "/home/dprince/glance/.venv/lib/python2.6/site-packages/sqlalchemy/engine/default.py", line 331, in do_execute
    cursor.execute(statement, parameters)
ProgrammingError: (ProgrammingError) constraint "image_members_image_id_member_key" of relation "image_members" does not exist
 'ALTER TABLE image_members DROP CONSTRAINT image_members_image_id_member_key ' {}