Playing a sound when mail arrives

Hi,
        I want to be able to play an au-file 
when mail arrives in a particular folder.

I have in my .procmailrc: (for testing this feature)

:0 
* ^From.*prabha
{ 
        :0 c:
        prabhanjan

        :0
        | cat > /dev/null; /bin/audioplay -V /usr/demo/SOUND/sounds/cuckoo.au
}

When I send mail to myself it is supposed to go to the folder
"prabhanjan" and also play a sound. 

When I test this by sending mail to myself and checking the procmail log,
I find that the mail goe sto my folder, but audioplay doesn't succeed.
Message is :

audioplay: error opening /dev/audio: Permission denied

I can play the sound from "sh" directly. 

Can someone tell me what is wrong ?

-Prabhanjan