http://cointelegraph.com/news/115374/the-ongoing-bitcoin-malleability-attack
Someone is using the transaction malleability bug to take advantage of businesses that accept zero confirmation payments.
But it's OK... https://www.reddit.com/r/Bitcoin/comments/3nfb2y/eli5_for_double_spends_bitcoin_being_sent_twice/
it was recommended that people should wait for blockchain to confirm fully before adding on top of previous transactions.
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