An anonymous reader tipped us to news that several Bitcoin exchanges have joined Mt Gox in suspending withdrawals
after being forced out of sync with the Bitcoin network at large. After Mt Gox blamed transaction malleability
for forcing them to suspend withdrawals, miscreants started flooding at least Bitpay and Btc-e with bogus transactions. Quoting the Bitcoin Foundation: "Somebody (or several somebodies) is taking advantage of the transaction malleability issue and relaying mutated versions of transactions. This is exposing bugs in both the reference implementation and some exchange’s software. We (core dev team, developers at the exchanges, and even big mining pools) are creating workarounds and fixes right now. This is a denial-of-service attack; whoever is doing this is not stealing coins, but is succeeding in preventing some transactions from confirming. It’s important to note that DoS attacks do not affect people’s bitcoin wallets or funds. "