diff --git a/gestion/gen_confs/firewall.py b/gestion/gen_confs/firewall.py
index 85dd0832..1b07f943 100755
--- a/gestion/gen_confs/firewall.py
+++ b/gestion/gen_confs/firewall.py
@@ -617,6 +617,7 @@ class firewall_komaz(firewall_crans) :
                   'udp' : machine.portUDPout() }
 
         for proto in [ 'tcp', 'udp' ] :
+            if not ports[proto]: ports[proto] = ':'
             for port in ports[proto]:
                 iptables("-I SERVEURS_VERS_EXT -s %s -p %s --dport %s -m mac --mac-source %s -j ACCEPT" \
                 %(ip,proto,port,mac))