I'm going to bump this question and shorten it:

I would like to set up Simul Ring to ring my cell phone; I would also like unanswered calls to my cell phone to go to VOIPo for voicemail. Can both be done without putting the call in an infinite loop? This would require Simul Ring to recognize that a call is coming in through a "ring to" phone so that it does not continue to ring that phone.

Thanks.