--- a/mod_s2s_auth_fingerprint/mod_s2s_auth_fingerprint.lua	Mon Mar 25 03:54:32 2013 +0100
+++ b/mod_s2s_auth_fingerprint/mod_s2s_auth_fingerprint.lua	Mon Mar 25 06:40:05 2013 +0100
@@ -27,7 +27,7 @@
 	local session, host, cert = event.session, event.host, event.cert;
 
 	local host_fingerprints = fingerprints[host];
-	if host_fingerprints then
+	if cert and host_fingerprints then
 		local digest = cert:digest(digest_algo);
 		if host_fingerprints[digest] then
 			session.cert_chain_status = "valid";