Shadows and setting up a scene with final gather

[ididdy]

I am having problems with setting up a scene in maya 6, want an image of an object sitting on a white groundplane which is illuminated by an hdr image.

my problem is that the oblect being lit is not casting shadows on the groung plane.

I have a very simple scene with just the object sitting on a ground plane which is lit by an hdri.

Can anyone help,

Also as i am new to maya, how do you control the brightness of the hdri, in maya 6, when the new option is used (in the render globals).

Are there any tutorials for this method on the web?

Thanks

[failure]

Add a shadow casting light to your scene.