If Voipo did the 'confirm calls' feature, then all of your voicemail would end up in your Voipo voicemail box. If your cell phone's voicemail picked up the call, it would not be able to "press 1" so it would never receive the call. Once the voipo line recorded 4 or 5 rings (whichever your vmail is set for), voipo VM would take the call. This behavior is exactly how the (soon-to-be-defunct) CallVantage "Locate Me" feature works, and I'd like to retain this capability.