asterisk users - Jul 2004 - dropping g729 frames

I'm getting this error continuously when sending to a cisco 5300: 

frame.c:120 ast_smoother_feed: Dropping extra frame of G.729 since we
already have a VAD frame at the end

The connection is highly intermittent, sometimes there's a ring, other
times there is not.  Is there a way to completely disable vad support in
*?  

-g