DKIM bad format?

From: Matt Wiseman <mw_at_cyber2.com>
Date: Tue, 23 Apr 2013 10:35:01 -0700

Google is saying this:
       dkim=neutral (bad format) header.i=_at_accountfollowup.com;

here's my dkim sig
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=accountfollowup.com;
s=mail; t=1366737779;
bh=BXljuRQelkkw9MlQsyKcL2UwDWyeb27vBDfb5G1YxWc=;
h=From:To:Subject:Date;
b=iHZqOBFSpHBtVQr0FGqvgNdUurfDAVIz34t7YR3M2VC6DrsHg7h4MMs7lj4gfrusz
 nikI4WQHQIO0vIHGqhZAYAr2zSgkF94pbizRuJezBgE+U9p6iUb/h2YfJaKfZTM3qk
 e86vZsKRXoaIGIaZ6hEKX0zL8F0jy8k1G4RNESyU=


Any help would be appreciated!
Received on Tue Apr 23 2013 - 17:35:14 PST