The Grateful Dead's Bob Weir is pleading with Deadheads everywhere not to vote for Ralph Nader. Performing on Saturday in Boston, Weir told the band's followers to be sure to vote, but the exorted, "Don't vote for Nader. I know him. He's an a--hole," our spies tell us. The band then broke into "Johnny B. Goode," a theme song of the Kerry-Edwards campaign ...