Pennsylvania Secretary of the Commonwealth Pedro Cortes on May 2 issued a directive to election departments statewide about the possible flaw in Diebold Elections Systems Inc.'s AccuVote TSX e-voting machines. The warning was announced days after Diebold alerted Cortes' office to a "potential security vulnerability in the system installation and upgrade mechanism" of the AccuVote touch-screen systems.

Statewide, 3,338 of the touch-screen machines will be used in Tuesday's election; more will be installed for the general election in November, said a spokeswoman for Cortes.

According to Diebold, the vulnerability is in the AccuVote systems' PC card slot, where unauthorized software could be installed without detection. The slot makes it easier for elections officials to install upgrades to the TSX machines as well as Diebold's AccuVote TS models, a company spokesman said. He didn't provide a timetable for fixing the flaw.

In its note to Pennsylvania officials, Diebold promised to eventually create a software-based "permanent solution." The spokeswoman for Cortes said the Allen, Texas-based unit of Diebold Inc. claimed that there was a "very low risk" that elections could be affected in the meantime. But Cortes reacted quickly to ensure that Tuesday's elections run smoothly, she said.

The secretary's office called on all Pennsylvania counties to reinstall the machines' system software in order to overwrite any unauthorized programs that may have been downloaded onto the systems. It also supplied each district with memory cards containing ballot information, to insert into the affected slot to update the voting machines.