Update README.md

Author: Programie

README.md

@@ -8,7 +8,7 @@ Authorization is done using HTTP Basic Auth or using the *username* and *passwor
 
 The full URL looks like *http://dyndns.example.com/?hostname=myhost.example.com* (HTTP Basic Auth) or *http://dyndns.example.com/?hostname=myhost.example.com&username=myuser&password=mypassword* (URL variable auth).
 
-You may also specify the IP address using a GET variable (ipaddress=your.ip.address.here). Example: *http://dyndns.example.com/?hostname=myhost.example.com&ipaddress=79.206.99.18*
+You may also specify the IP address using a GET variable (ipaddress=your.ip.address.here). Example: *http://dyndns.example.com/?hostname=myhost.example.com&ipaddress=79.206.99.18* or *http://dyndns.example.com/?hostname=myhost.example.com&ipaddress=2003:66:ef5d:9300:5899:991b:8542:b19f*
 
 PHP DynDNS also supports IPv6! To update both, the IPv4 and IPv6 address, just make two requests (one with the IPv4 and one with the IPv6 address).