asterisk users - Jun 2005 - Dropping Frame of G729

Here is the setup:

  Phone -SIP G729-> AsteriskA -IAX G729-> AsteriskB -SIP G729-> Carrier

The call completes but AsteriskA prints on the screen a ton of those 
"Dropping Frame of G729" messages starting about 5 seconds into the
call:

Jun 10 11:17:14 NOTICE[14277]: frame.c:135 __ast_smoother_feed: Dropping 
extra frame of G.729 since we already have a VAD frame at the end
Jun 10 11:17:14 NOTICE[14277]: frame.c:135 __ast_smoother_feed: Dropping 
extra frame of G.729 since we already have a VAD frame at the end
Jun 10 11:17:14 NOTICE[14277]: frame.c:135 __ast_smoother_feed: Dropping 
extra frame of G.729 since we already have a VAD frame at the end
Jun 10 11:17:14 NOTICE[14277]: frame.c:135 __ast_smoother_feed: Dropping 
extra frame of G.729 since we already have a VAD frame at the end

I'm guessing the Carrier is causing this? But I don't see any messages 
like this on AsteriskB.

Any ideas?

Thanks,
-Matthew