if it is showing 'option 128 missing' on the phone then it is not in teleworker mode. Indeed there are firewall rules that need to be added to the firewall at the MBG side (depends on the server setup) however, lets start at 101, reboot the phone holding down the 7 key and put the phone into teleworker mode. Enter the external IP of the teleworker server and store the changes. post back with the outcome