Yet it may take hours for Mt. Gox to help you out.
At what point did you think you were dealing with a "normal, professional company" in Mt. Gox?
What did it for you?  Their over-the-top web design?  Advanced trading tools?  Sophisticated, deep market?

They're not Citibank.  Either they've taken off with the money and all of this is meant as a stall tactic, or (my guess) they're flogging their fingers off trying to completely overhaul their system.  If you think their responsiveness has been or is unacceptable, take your business to one of the "normal, professional" exchanges.