Max MIDI bus broken?

Two simple patches -
1. kslider to makenote to noteout - noteout set to "from maxmsp 1"
2. notein (to pack i i i to message to see what's going on) - notein set to "to maxmsp 1"

ie using the max midi buss to send messages from one patcher to another.

Play the keyboard in patch 1 - nothing comes out of notein in patch 2.

This _is what the to/from maxmsp busses are for, isn't it? It's not something I'd normally do, but I wanted to use the max midi buss to receive messages from someone else's patch (which is sending data out over midi). I can replace the midi with send/receive pairs if needs be, but using midi would be simpler in this instance.

I'd have thought the internal midi busses would be "just there" (they are turned on in the midi set up dialogue) - is there something else I need to do to get them to work?

puzzled

Edit - I just loaded up an app version of a patch, with it's own to/from midi buss, and that works. So is it the case that the buss works between apps, but not between max patches?

David