That is too much of a pain-in-the-ass. I created a site a while back to let users port their number and then manage allowed incoming calls via the web. Originally it was designed so that people moving out of their area codes could forward landline calls indefinitely to their new number, but it could easily handle 'whitelists'. The server is getting smashed with hits right now, but check it out at http://www.callpass.net/
That is too much of a pain-in-the-ass. I created a site a while back to let users port their number and then manage allowed incoming calls via the web. Originally it was designed so that people moving out of their area codes could forward landline calls indefinitely to their new number, but it could easily handle 'whitelists'. The server is getting smashed with hits right now, but check it out at http://www.callpass.net/