It would be strange that you can log in to your account, but not to your MyPlane site, as both use the same login/password combo as the game account.
Not being able to log in to the game may have different reasons (e.g. developers locking the login during maintenance), but the MyPlane site should be available all day.
You could try to reach a developer with access to user tables in the database by visiting channel #planeshift-gmtalk in the Freenode IRC network. Use names of "voiced" members there to greet them, that may ring their bell.