Anyone who needs immediate access to their funds shouldn't be using MtGox in the first place.
Maybe you got hacked and the hacker changed password to lock you out.
There are a ton of threads here every week about people being locked out of their MtGox accounts due to AML issues, suspected fraud, and accounts having been phished. It's kind of ridiculous at this point not to assume this could happen to you, operate accordingly and limit your MtGox exposure so that delays in being able to access your MtGox funds aren't going to cause you any real life problems.
These issues are well known and have been well publicised in these forums (along with regular issues regarding certain withdrawal methods) yet people continue to ignore the well known risk of their funds not being immediately accessible.