Plug mi node inside Lens shader - how?


Just a strange issue. I'm trying to script in mr subset automation but I cant plug anything in sigh. Can any1 have a look at my script please.

renderers.production = mental_ray_renderer()
SubSnode = Render_Subset_of_Scene_Masking__mi  name:"SubS"

And then I will be adding objects to it etc etc but I cant get past 1st issue of connecting the nodes. Any idea how can I hock them up together?