From www.wdwinfo.com

Disney responds to counterfeit FastPass
Mar 1, 2008

Disney has verified the rumored crackdown on fake FastPasses being sold via online auction sites.

While calling use of the counterfeit passes "infrequent" and "isolated" the current test of pass barcode scanners in Disney World indicates that this problem is a growing cause of concern.

Unlike the FastPasses issued in the parks, most of the fakes are "admission re-entry" passes which are not dated and can be used at any of the park's attractions.

Until the new scanning systems under development are in place, Disney Cast Members are instructed to take a closer look at the passes being used by visitors.