I must admit, there were two minor api changes in the module.. however.. and this is a big difference

eth0 1.2.3.4
ppp0 192.168.1.1 <-> 192.168.1.254

If the MMSC ip address is 1.2.3.4 you cannot (afaik) use iproute2 to instruct the system to route via 192.168.1 254 as it is treated locally. With the ipt_route module, you can.

You're right about avoiding experimental modules, but the module itself is quite simple. Without (usable) namespace support in the kernel it is a nasty hack any which way.. I was aiming for something that could run in paralell to a wifi connection or a different ppp connection and be totally unnoticable from a user perspective. I do see you point though, but making it transparent to the user is important too.. imho

This weekend I'll try and get something working with my N810 You're right, working on x86 is one thing, but it must be thoroughly tested on arm!

Doing it through userspace as you mentioned could be a viable alternative.. netfilter lets you attack a packet *almost* prior to routing which means you can hit things that would resolve locally without serious routing.. iproute2 is pretty focused on the routing layer..

As I said, it was just a suggestion, but I'm more than happy to do some serious leg work here!