2009 Oct 27, 9:47"We're excited to announce that you now have the choice to get Google Voice with your existing mobile number OR with a Google number." You can use their voicemail features with your existing phone
number.
via:connolly google voice phone cellphone voicemail blog 2009 Aug 3, 9:37"If you have T-Mobile USA, you can program the time your phone rings before it rolls to voice mail, but it isn't at all intuitive."
tmobile cellphone phone voicemail howto
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