I've just downloaded FlightGear today and everything is working well, except I can't get the rudder responding to joystick commands.
I am using an unbranded joystick which appears as "Joy Stick": Surprisingly it works well (calibrates fine, can identify and map all buttons from within FlightGear) and any other control I map to it works perfectly. The rudder also works perfectly from the keyboard commands. Weirdly however, I cannot get the rudder working with the joystick on any axis or buttons. I've worked through the easy troubleshooting stuff on the Wiki and as far as I can tell there are no other issues with either the game or joystick.
I'm using Windows 7 64-bit with a AMD Radeon HD 4200 graphic card and the latest FlightGear release, if any of that helps.
Thanks in advance for any suggestions.