Hacking cell phone buttons Answered

Hey there everyone,
I'm trying to hack a cell phone such that I can simulate a button being 'pressed' by some other external switch.  I simply want to wire a lead on either side of the button so that I can essentially short it out (and then set it up so that the call is set up off of other circuit triggers such as 555 timer).

If anyone has a recommended type of phone to use for prototyping purposes, I'd love to know.  Otherwise I'm just using a verizon pre-paid phone I picked up from 7-11 (will attach picture shortly)