POSB bank charging $2 for excess ATM use?

inSing.com, 9 Oct 2011

Is POSB bank imposing a $2 fee for customers who make more than four ATM withdrawals a month?
A "poster" spreading via Twitter appears to be stating this rule.
It says, "The first 4 ATM cash withdrawals in each month are free. There will be a $2 ATM withdrawal fee should you exceed 4 ATM cash withdrawals, including at ATMs overseas." Full story