diff --git a/port-forwards.default b/port-forwards.default
index 1a4d8a4..aac7602 100644
--- a/port-forwards.default
+++ b/port-forwards.default
@@ -1,3 +1,6 @@
 # Format is:
 # External interface:Src IP:External IP:External port:Internal ip:Internal port
+# If you want to allow any source IP or a dynamic IP external IP, use 0/0 and not 0.0.0.0
+# (iptables translates 0.0.0.0 to 0.0.0.0/32 which won't work)
+# Rename this file to port-forwards before using!
 #eth0:4.2.2.0:4.2.2.1:8080:tcp:192.168.0.100:80