cell phone auto dials with speaker on?

["tata" <tatadata@xxxxxxxxxxx>]

Hello,

I'd like some help settling an arugment that has recently occured
between friends.  Seems that two friends were driving somewhere
together and during the trip Passenger says "...my cell jostled during
the ride and it autodialed M's number".  This happened while Driver was
telling Passenger some VERY personal stories.  M picks up the phone and
hears only voices, thinking it was a party line, she listened and
eventually it dawned on her who the speaker was.  Now some backup facts
might be in order...M is also in the same tiff with Passenger...they
haven't spoken in weeks and in fact, M has since moved and this call
came in on her new number, which Passenger had never called before.  Of
course, the speaker phone must have also been turned on.

My question...is it possible for a cell phone to autodial someone from
a contact list just by "jostling" the cell phone?  Passenger says M's
phone number is the second on the list...That means, while sitting
quietly in the car, Passenger jostled around in her purse enough to tap
her contact list, down two, dial, and open speaker phone...have I got
that right?  I don't know what brand cell she's using, but having had
an exposed keypad cell myself, I must say this sort of sequence never
happened to me.

Anyone got a good reason this could be an accident?

Thanks!!!