Update: Shared Coin has now been re-enabled! Thanks for your patience.
We have temporarily suspended Shared Coin transactions while investigating some transactions that are “stuck”. The particular transaction in question is https://blockchain.info/tx-index/115315411/10. Rebroadcasting this transaction in bitcoind results in Error code -22.
Apologies for any inconvenience this may have caused. Any help from the community would be appreciated as well. Feel free to contact: cz at blockchain.info, if you feel you have a solution or can help. Please do not spam. Thanks.