Using Blockchain.info for mutlisig transactions?

[Barrack Obama]

Ok, So I was thinking about this multisig transaction problem and heres what I came up with.

We make blockchain.info accounts with secondary passwords, and email for verification of withdraw.

Buyer deposits the amount into the blockchain account. Vendor ships product.

We give buyer, and seller blockchain info identifier and password. We give the buyer the secondary password to make withdraws.

The vendor get's the email associated with the blockchain account, we tell him to change the email password so he can verify all outgoing transactions to make sure it's going to his address.
Once the buyer receives his item, he goes into blockchain account and using the secondary password sends the payment to the vendors address.
The vendor is able to approve the transaction to his address, and the payment goes through.

If for whatever reason the buyer receives his product but doesn't bother to come back on to verify the transaction my business has access to the blockchain account and secondary password where we can then send out the payment to the vendors address, and the vendor can confirm it in email.

Unfortunately I tested this and email verification for output transactions doesn't seem to be an option. It only lets you know via email of a sent payment. Anyone know any other wallets where this might work?

Thank You.