After much searching and experimenting, I finally got my Treo 650 to
wait until I press the answer button on my H700 headset before answering. At the end of the pairing process, choose "Car Kit" instead of "Headset" when asked to select the type of handsfree device. Go figure. See the review and comments at:
http://blog.treonauts.com/2006/08/motorola_h700_b.html
Thanks to Andrew at TREONAUTS.

Buddha35