Visa Australia and New Zealand has postponed implementation of a security requirement that merchants accept only personal identification numbers for card-holder verification. The decision is one of a number of setbacks to the roll out of the payment system group's security strategy.Visa had set a start date of April 1 for merchants to stop accepting signatures for verification with card payments. Its view is that a PIN is safer than a signature.A Visa spokesperson said a new start date for the rule was yet to be set, but it would be some time next year. Migration to PIN-only verification is underway, however, and will continue.In 2009, Visa announced a seven-point plan to strengthen the security of its payment system. The key to the plan was a move to chip card issuance and to upgrade ATM and point-of-sale infrastructure, to enable all equipment to read chips, rather than magnetic stripes.Visa said yesterday that it has met its mandate for ATMs being chip enabled, and about 90 per cent point-of-sale terminals were chip enabled.Visa set a deadline of April this year for all Visa cards to carry chips. It has missed that deadline.The spokesperson said all Visa card issuers are sending out new cards with chips, but there was still some changeover to be completed for issued card stock.Another of the requirements in the seven-point plan is that all merchants taking payments online, by telephone or by mail order, must (as of January 2011) check the three-digit card verification code on the back of the card.The Visa spokesperson said compliance with this requirement was high and was continuing to increase, but there is anecdotal evidence that compliance is limited (this reporter's own experience would put the compliance rate at about 50 or 60 per cent).Visa said it has met its goal of having issuers enrol all their cards in Verified by Visa, a password system for online shopping.