I found this on the 700w users forum, it works on the 700p as well.

Verizon just announced that they'll be rolling out a feature called CPOP which will allow you to receive phone calls even during an active 1x data transfer - EVDO already supports this....but yeah, very cool...
Press *765 after 3 beeps it will disconect, you should be activated. It worked for me.
Campbell