diff --git a/lib/iptables.inc b/lib/iptables.inc
index 7883cd6..74e9878 100644
--- a/lib/iptables.inc
+++ b/lib/iptables.inc
@@ -410,6 +410,7 @@ function enable_forwarding {
 			${VER_IPTABLES} -A ${FwdFilter} ${protocol} ${srcinterface} ${srcaddress} ${srcport} ${syn} ${dstinterface} ${dstaddress} ${dstport} ${conntrack_state} -j ${action}
 			[[ ${bidirectional} == "yes" ]] && ${VER_IPTABLES} -A ${FwdFilter} ${protocol} ${revsrcinterface} ${revsrcaddress} ${revsrcport} ${syn} ${revdstinterface} ${revdstaddress} ${revdstport} ${conntrack_state} -j ${action}
 		done < "${FWCONFIGDIR}/ipv${IPVER}/forward.conf"
+		unset action srcinterface srcaddress dstinterface dstaddress bidirectional srcport dstport protocol syn
 		${debug} ${DebugColor} "${FUNCNAME}:${DEFAULT_COLOR} done"
 	fi
 }