Redeemable unspent output / multi-sigs?

[DougPeters]

How can I tell if an incoming payment is redeemable by my receiving address's private key through the RPC API?

My concern is receiving a multi-sig tx which I will process in my program but then won't be able to redeem, so for now I call gettxout for every single unspent output not generated by my program and check that the "reqSigs" return parameter equals to 1. Is this the right way to do it?