While on Vacation in Manila, I am receiving voicemails. I have no data plan and roaming is turned off. I can't access my mailbox while I am out of the country. Will I be subject to additional charges? I have an iPhone 4s which I had unlocked a few months ago, so it would work with my Koodo sim card. Initially, I had the iPhone activated through Rogers many years ago. My current plan is approx. $45.00/month and it has since been grandfathered (no longer available). 600min on calls is the only info. that I remember.