WLM won't use animated gif for signature

I used to have a great animated gif as a signature in XP with live mail. I now have vista and the same file won't work. I have tried everything I could find in a 3 day google search. The best I could do was to get a red X to display. I can get the signature to work if I save it as stationary but I would rather have it inserted as a signature.

Thanks;
Steve