The Ethereum community has elected to do a hard fork in order to resolve the DAO exploit. The MainNet block on which the hard fork will occur is set at 1920000, which should be reached on July 20 or 21 depending on your time zone.
In an email statement to clients last week about the hard fork we said:
ETH deposits and withdrawals will be disabled approximately 1 hour before the hard fork activates. Trading will continue as normal during the fork. All ETH on Kraken after the fork will be tokens of the winning chain (i.e. the chain with the most work on it). ETH deposits and withdrawals will be enabled again once the winning chain has become clearly evident.
Some interpreted this statement to mean that we would not grant access to balances on the non-dominant chain under any circumstance but this was never our intention. The statement was written from the standpoint of a “winner take all” scenario where the non-dominant chain dies out fairly quickly. Since the outcome of the fork may be more complicated than this, we want to make a number clarifications here and assure everyone that we are making preparations to be ready for any outcome of the fork and will act accordingly.
How long will it take?
Although the process may go smoothly and quickly, we want everyone to understand that we will be very cautious about waiting for a clearly dominant chain (with the most work on it) to emerge before enabling ETH and DAO funding again. We think this is unlikely, but depending on how things go, we may have to wait several days or more to be safe. You should not send any Ethereum or DAO deposits to Kraken until we have enable deposits. You can follow us on twitter (https://twitter.com/krakenfx) or our status page (https://status.kraken.com/) to learn when funding is enabled again.
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http://www.financemagnates.com/cryptocurrency/exchange/kraken-freezes-disables-ethereum-trading-until-dao-fork-ends/