user21183: I am writing a project in Ruby using JSON-RPC to communicate with blockchain.info. The API is available here: https://blockchain.info/api/json_rpc_api
Is it possible to create a op_return txout using the given JSON-RPC API ?

user7267: Blockchain.info and bitoind/qt out of the box doesn't support pushing transaction out with the OP_RETURN op code. They will mark the transaction as invalid and refuse to broadcast it.
I have an open source project with a program that will push out transactions to the network directly at https://github.com/kaykurokawa/pushtx.  It doesn't do any error checking on the transaction so transactions with OP_RETURN will get relayed.
I've successfully used this in combination with pybitcointools for crafting a transaction with OP_RETURN in it.

21183: <p>I am writing a project in Ruby using JSON-RPC to communicate with blockchain.info. The API is available here: <a href="https://blockchain.info/api/json_rpc_api" rel="nofollow">https://blockchain.info/api/json_rpc_api</a></p>

<p>Is it possible to create a <strong>op_return</strong> txout using the given JSON-RPC API ?</p>
 7267: <p>Blockchain.info and bitoind/qt out of the box doesn't support pushing transaction out with the OP_RETURN op code. They will mark the transaction as invalid and refuse to broadcast it.</p>

<p>I have an open source project with a program that will push out transactions to the network directly at <a href="https://github.com/kaykurokawa/pushtx" rel="nofollow">https://github.com/kaykurokawa/pushtx</a>.  It doesn't do any error checking on the transaction so transactions with OP_RETURN will get relayed.</p>

<p>I've successfully used this in combination with <a href="https://github.com/vbuterin/pybitcointools" rel="nofollow">pybitcointools</a> for crafting a transaction with OP_RETURN in it.</p>
