Recent simh versions no longer need any external program to work with tap devices. I saw that - simh v3.9, I think. I'm still using 3.8-3 (I have some local patches that I don't want to redo just yet). It's a good suggestion, but the fact is that the old simh worked just fine with Ubuntu 10.04 - it's the upgrade to 12.04 that broke things. Bob