It depends which phone company you are with John.
I heard Vodafone pay as you go does work , but Orange pay as you go definitely did not work in Davao last July, even with my phone unlocked. It all depends on whether the phone companies agree with each other or not.
On one trip to Perth , Australia, my phone was automatically connected to Vodafone even though I am an Orange customer. [img]style_emoticons/<#EMO_DIR#>/huh.gif[/img]
Still cheaper to buy a SIM card out in the Phils