The Bitcoin network is currently experiencing an irreconcilable fork
between Bitcoin 0.8 and <0.8 nodes due to a block being mined by a
Bitcoin 0.8 node which an elevated blocksize which older nodes are
unable to handled.

This issue will be resolved by mining power moving to the pre-0.8 fork
and making it longer.  Until this is resolved all transactions at and
beyond block 225439 should be regarded as unconfirmed.

Miners must move their hashpower back to 0.7.2 (or before) nodes or
their blocks will be orphaned.  Once the pre-0.8 chain is longer
operation will resume as normal and a patch will be issued for 0.8 to
avoid triggering this issue.

Please see the Bitcoin-dev mailing list or contact me if more
information is required. I will send out another email once the issue
is resolved.