I just take Yoigo in spain to have ISP and I send ZTE F680
I bought a Dyndns for don't buy a public IP but it seems that router dind't works fine with standard configuration.
Some one know good paremters? (custom server, Curstom URL, exact host name (with .dynsdns.org or not), provider name (with @mail or not))
This is documented in the Dyn update API.