Hello Mt.Gox Users,
At approximately 23:00JST on June 23, 2012, trading became unavailable due to an invalid trade order which was not checked correctly by the Add Order API. The trading system however, detected this and halted itself to wait for further instructions, resulting in this outage.
Trading is now back to normal. We apologize for the inconvenience our users have suffered because of this outage and would like to thank you for your patience through this issue. If you have any further questions regarding this matter, please do not hesitate to contact Mt.Gox Support.
Mt.Gox Team