The U.S. arm of credit and debit card giant <A HREF="http://www.eweek.com/article2/0,1895,1939301,00.asp?kc=ewnws031706dtx1k0000599">Visa International has issued an alert</A> for flaws in cash-register software made by Fujitsu Transaction Solutions that could put sensitive cardholder information at risk. According to a report in The Wall Street Journal, the bug can cause the inadvertent storage of customer data--including secret PINs--within the point-of-sale software installed in retail locations. The report said Visa USA sent the warning to "merchant acquirers" that process card transactions for some of the biggest names in retail and urged users to apply a software upgrade from Fujitsu to fix the flaw. Officials from Visa USA and Fujitsu could not be reached for comment at press time but, according to the newspaper, the confidential alert was sent several days ago to raise awareness about the bug.