official osx avrdude with rfduino extensions built on snow leopard 10.8.7 with xcode 4.2.  The osx avrdude built on mountain lion is not backwards compatible with prior releases of osx.  I experimented with a few xcode/gcc compile options, but was unable to get it working (if someone knows how to do this, please post in the forum), after a while it was just easier to recompiled under snow leopard instead :)