Audio - INT Left / EXT Right - How do I make this work?

[handbanana]

Hey all, I posted a detailed thread as to the root of my issue here: http://www.magiclantern.fm/forum/index.php?topic=1973.0

But basically, given my broken audio input (won't switch to INT when no EXT present, EXT is loose) I would love to run my external mic in one channel while recording with the internal in the other. But when I use this setting, only the internal records - I imgaine this is because in external mode the mic also records to the Left channel. Is there a way I can force the external to the right (without having to use extra cables to switch them) or force the internal to the right?