I have a VS-GW1600 V2 with WCDMA ports and the latest firmware version available (2.1..
I have a problem when sending SMS over HTTP: The JSON response result message is always "sending" and for playsms this is a failed message. Finally the message is sent, but the JSON response is immediate with this result
alternatively, I have VS-GW1202 GSM also with the latest version (2.5.4), and here the behavior is as expected: The JSON message does not appear until the message is not sent and reports result=success