First, a fix:

===
diff -up polkit-0.107/src/polkitagent/polkitagentlistener.c.jx polkit-0.107/src/polkitagent/polkitagentlistener.c
--- polkit-0.107/src/polkitagent/polkitagentlistener.c.jx	2012-04-24 12:05:34.000000000 -0400
+++ polkit-0.107/src/polkitagent/polkitagentlistener.c	2012-10-08 13:17:27.884850539 -0400
@@ -260,10 +260,9 @@ server_new (PolkitSubject  *subject,
   if (!server_init_sync (server, cancellable, error))
     {
       server_free (server);
-      goto out;
+      return NULL;
     }
 
- out:
   return server;
 }
 
===

Note that otherwise we return a freed server object.  Since later in polkit_agent_listener_register_with_options we check against NULL to determine failure, this makes for sad times later when we call server_free() on it again.