Arduino, matlab and servo control

Hi,
Im new about the arduino language. I have tried control the LED by using the matlab through Arduino, it work well to me, but cannot control even move the servo motor as i refer to the arduino forum the previous forum about arduino matlab servo.
There are my steps and code in order to control and interface.
1.dowload the arduino i/o support package and installed it.
2.connect the arduino to PC via ubs port
3.dowload and install the arduino software and 'upload' the adiosrv into arduino duemilanove (also try in romeo) board
4.type arduino in the matlab and it connect successful.
5.and then type "a=arduino('COM8')", "a.servoAttach(1)"and "a.servoWrite(1,50)" to move the servo motor 1(pin 9) from 0 to 50 degree.

but it seem does not work at all.
my question are:
1.is there any steps that i miss out?

2.any software is required others than what i mention above?

3.the romeo or the duemilanove that assign to "a.servoAttach(1)" is represented pin 9 and "a.servoAttach(2)"