Index: elixir/trunk/elixir/relationships.py
===================================================================
--- elixir/trunk/elixir/relationships.py (revision 297)
+++ elixir/trunk/elixir/relationships.py (revision 307)
@@ -336,4 +336,6 @@
 from sqlalchemy.ext.associationproxy import association_proxy
 
+from py23compat import rsplit
+
 import sys
 import options
@@ -419,5 +421,5 @@
                 self._target = self.of_kind
             else:
-                path = self.of_kind.rsplit('.', 1)
+                path = rsplit(self.of_kind, '.', 1)
                 classname = path.pop()