[SR-Users] app_python rewrite_ruri - BUG: do_action bad set*()

Hi, I'm having problems getting started with the app_python module. I'm getting the following in the logs: 5(8890) : <core> [action.c:785]: BUG: do_action: bad set*() type 14 5(8890) ERROR: <core> [action.c:1568]: run action error at: :0 5(8890) ERROR: app_python [python_msgobj.c:115]: Error in do_action 5(8890) ERROR: app_python [python_support.c:38]: python_exec2: Unhandled exception in the Python code: 5(8890) ERROR: app_python [python_support.c:78]: RuntimeError: Error in do_action My Python module is very basic: class Router(object): def child_init(self, child_id): return 0 def route(self, msg): msg.rewrite_ruri('sip:1000@1.2.3.4:5060') return 0 def mod_init(): instance = Router() return instance I've tested this in Kamailio 3.2 and 3.3. Can someone point me to what I'm doing wrong? Many thanks in advance, vtone