It harkens back to the best practices listed in the February 2005 ODP guidance. The Fed has recently said that it feels the best practices are still best practices (unless regulations have superseded them). It probably can only work at your own ATMs, but it's also wise to post a notice at the ATM to the effect that ATM transactions that overdraw an account may result in OD fees.
John S. Burnett
Fighting for Compliance since 1976
Bankers' Threads User #8