Soundproblem

Hi there!
I have a problem witch I only found a few non-functional scripts to solve.
I want irssi to beep as soon as someone pm's me och highlights me.
Searched the web a bit but as I said I only found a few scripts and I 
couldn't get them to work.
So if someone can help me how to set up irssi so I recieve a sound as 
soon as a pm or highlight comes up I would be glad.

Best regards
XeroXer