The National Post (Canada, eh?) says the Nats haven't approached the Blue Jays about LaCava:
Hold off on the goodbye parties for Tony LaCava, the Toronto Blue Jays director of player personnel.
LaCava has been rumoured to be the next general manager of the Washington Nationals, assuming the Nationals let current GM Jim Bowden go. But sources say that Washington has neither asked for nor received permission from the Blue Jays to speak with LaCava.