Comedian Rodney Dangerfield may not get any respect, but he is about to hear the sweet sound of “I do” — and not, by any means, for the first time. Dangerfield, 78, who is on the mend following two surgical operations earlier this year, plans to renew his wedding vows with his second wife, Joan, 46, this month at the Los Angeles premiere of his latest movie, “My Five Wives.” In it, he plays a polygamist. “I’m excited about it,” Dangerfield told Reuters yesterday. “I tell my wife, ‘I married you when I was drunk,’ so she’s insisting that I repeat the vows when I’m sober.” Officiating at the upcoming ceremony, says Dangerfield, will be his costar, Andrew Dice Clay. Guests will include others from the movie, including Jerry Stiller, Molly Shannon, Tim Conway and Harvey Korman.