Are you sure it isn't just the standard warning text they send when you are out of the UK?
I received the following when in theUS last month:
That is just a standard text warning you about the potential costs. I used my 02 iPhone whilst in the US on wifi only and was not charged anything extra, even though I received the text above.
I received the following when in theUS last month:
Using the web outside Europe costs £6/MB. We'll tell you when you've spent £20 and then again at £40. We won't charge you more than £40 on your current bill and you can use up to 50MB
That is just a standard text warning you about the potential costs. I used my 02 iPhone whilst in the US on wifi only and was not charged anything extra, even though I received the text above.