Hey Daniel,
we are working on our separate branches in openbsc: daniel/gprs-iu and neels/cscn.
Merging them will be nontrivial, at least because I have moved gprs/sgsn_iu.c to new libiu/iu.c and include/.../iu.h. That's because some of the stuff there is useful outside of the gprs scope.
Otherwise I've not changed the code much, you have at least a little, so before we potentially further complicate the changes, we may benefit from consolidating our branches, sooner rather than later...
Though my cscn code doesn't do anything useful yet, it is in a separate new subdir, so merging it to master wouldn't break anything. Merging both our stuffs to master is what I would suggest.
If you merge to master first I volunteer to rebase mine and take on the hard half of the merge myself. OTOH, if I'm faster ... ;) (More precisely, I'll bump this in at most two weeks, so plz go for it.)
Opinions/strategies welcome!
~Neels