BART is calling on its unions to reopen contract negotiations because of what its directors say is an expensive mistaken agreement on paid medical leave that now threatens to derail the pact that ended a four-day strike last month.

BART directors met in closed session Friday in a hastily called meeting to discuss what they call an unintended "error" in the contract that gives the system's workers up to six weeks of paid time off for personal or family health problems.

"We've reviewed the chronology of events concerning Section 4.8 and are convinced that it was never the district's intention to include the disputed Family Medical Leave Act proposal in the contract," Tom Radulovich, president of the BART board, said in a statement after the three-hour session. "We have directed the general manager to go back to the bargaining table and continue a discussion with union officials in an attempt to resolve the matter."

(Hat tip to Felix)