Forwarding SMS received from 'unknown sender'

[mr.BeBoT]

Is there a reg hack to enable the forwarding of SMS received from an unknown sender. I tried searching with relevant terms but came up with nothing. I'm hoping it's just some value in the registry that prevents it.

For an example of an unknown sender, use the sprint website to send yourself a text message (Bottom right corner) and you will receive it as unknown sender 'greying' out the reply options.

thanks in advance.