Folk,
The story I read referred to a software glitch resulting from unusually high
volume over the Labor Day weekend.
Most ATMs use OS2 (stand around one until the maintenance person re-boots
it).
My WAG (wild a** guess) is a fixed length field somewhere, say X,XXX,XXX,
and the network had 10,000,000 whatevers over the Labor Day holiday that was
then repeated when it came back up due to the pent-up demand from the system
being off line.
When was the last time you took a look at any data that increments in fixed
length fields?
Your mileage may vary.
-Al