adsp fail

From: Benny Pedersen <me_at_junc.org>
Date: Wed, 12 Dec 2012 21:55:34 +0100

Authentication-Results: duggi.junc.org; dkim=pass reason="1024-bit key"
        header.d=junc.org header.i=_at_junc.org header.b=MWteHqMS;
        dkim-adsp=fail

posting on postfix maillist gives this error, it used to be adsp pass,
what is my error here ?
Received on Wed Dec 12 2012 - 21:03:24 PST