No shadow from image file wt alpha

Hi all
Am new and think I just stuffed my first post. Sorry. But this is my problem.
I am trying to put a graphic with alpha onto a plane and have the shadow cast by the plane be that of the alpha. I have got graphic on the plane with alpha no problem, looks good, but I get the shadow of the plane not the graphic. Please help I have been trying to figure out for ages. Maya 5.

Maya depthmap shadows will not react to alpha... Use raytraced shadows instead.

Thanks a lot. It works.
suzanne

Hey there. I am having a werid problem with this. I have a poly plane and an image with an alpha (both targa and pngs give me this result). I am using ray trace shadows. The image I have textured on plane is casting a shadow, which is what I want but the Poly plane is also casting a shadow about half the intesity of the graphics. This I don't want, just a nice clean shadow from the graphic image. Thing is I have sucessfully achieved in another set up and can't see what I am doing wrong in this file. Any help I appreciate it. I can post sml jpeg of the problem to make it clearer waht is happening... thanks
suzanne

turn shadow attenuation to 0, also make sure you mep your specular channel with your alpha