Sorry if I am being stupid but how do you "create" them?
Not stupid, just ignorant, which everyone of us were at some point.
bitcoind createmultisig
He wasn't asking how to create the multi-sig address, but how to create the scriptPubKey and redeemScript.
I've tried to follow Gavin's script to create a multi-sig address and spend the coins I sent to it, but I can't figure out how to create a transaction. Signing the raw transaction doesn't work for some reason. If someone could look at this and tell me what I did wrong, I'd be extremely grateful:
http://pastebin.com/gkqF2Lh8 . Feel free to "steal" the 0.0095 BTC as long as you explain me how you created the transaction and what I did wrong.