When temperatures dropped last week, rumors flew like snowflakes that the city's parking kiosks were suffering from the cold. Perfectly valid SmartCards and credit cards are being rejected by the machines that have replaced meters on dozens of Center City streets.

There has been a malfunction, but weather is not to blame, said Richard Dickson Jr., senior director for strategic planning and administration at the Philadelphia Parking Authority.

"Two weeks ago, we installed an upgrade to our software," he said. That technological improvement created a glitch. "Our engineers are working on it. A new software upgrade will be installed by the end of next week."

During the intense shopping period before Christmas and the frenzy of returns and exchanges and bargain hunting that has followed, curbside spots have been at a premium.

And the parking authority's minions have been as fierce as ever. Not only do the violation envelopes appear on a windshield within seconds of the time limit's expiration, there are reports of people getting ticketed while they are half a block away, standing in line at a kiosk to pay for parking.

The authority's problem is not an opening to park for free, however. Drivers are expected to pay - somehow - to park, either by using old-fashioned cash or by inserting a credit card when a SmartCard won't work or vice versa.

If city drivers are upset, they don't seem to be registering their complaints with the PPA.

"Since the beginning of December, we've only received 24 complaints about SmartCards not working at the kiosks," Dickson said.

Yesterday, he was unable to retrieve information about complaints involving credit cards.

When Smart Cards began in 2003, $150,000 worth were sold. Last year, Dickson said, sales reached $2.5 million.