Setting phone to use google voice for all outgoing calls

[whitenack]

I just got done setting up my wife's new phone and my new phone (HTC Aria). I have google voice numbers for both, and setup google voice apps on each phone. I set the settings to "use google voice for all outgoing calls". On my phone, so far, all of my outgoing calls have used google voice. However, for my wife's phone, some calls use google voice and some calls don't.

Does anyone have any thoughts?

 

[whitenack]

Or, an acceptable solution would be if I could somehow change the caller ID function to show my GV number on outgoing calls instead of my carrier number. I see a setting in GV to do this, but it says it has to send my phone an SMS message, which I don't want to do. Is there a way to get around the SMS way of doing it? SMS's cost money.