Bomb from Starhub!

Got the shock of the day after seeing my Starhub handphone bill.
$2425.58 for 236MB 894Kb of data usage!!!
Faint faint faint!!!
Luckily, it was capped at $88. $2387.58 was deducted from the bill.
My wife said I am like those people appeared on the newspaper.
Charged for high data usage, unknowingly.

Thought I off the Edge data usage on my iPhone?
And I only use WiFi to surf the web and check email?
Don't feel like calling Starhub to check.
They will sure tell me that I did use up that amount of data.
Waste my time.
The only thing I did was to remove the 'shwapint' from the Edge setting.
No setting. I will only input it manually when I need to use it.
That's the only way to make sure that it doesn't logon to the Edge network by itself, when there isn't any internet access.

Just my luck...............