In fixing bug #446 [1], the output for unspecified proto was changed from "all" to "0".  This reverts to the original behaviour, and closes bugzilla #543. (Phil Oester)
diff --git a/iptables.c b/iptables.c
index 60ddc2d..893b02d 100644
--- a/iptables.c
+++ b/iptables.c
@@ -232,6 +232,7 @@
 	{ "esp", IPPROTO_ESP },
 	{ "ah", IPPROTO_AH },
 	{ "sctp", IPPROTO_SCTP },
+	{ "all", 0 },
 };
 
 static char *