Special birthday

LEO DiCaprio (above) is jetting to the Caribbean this weekend for model girlfriend Nina Agdal’s 25th birthday. Spies tells us DiCaprio, Agdal and a few of her pals boarded a private plane at Teterboro Airport on Friday. “He just hitched a ride, but it’s not his plane,” a source said of the eco-warrior actor. The couple, who have been together since July, has been seen in farflung locales. In November they stayed at a lavish resort in French Polynesia with DiCaprio’s mom, Irmelin, for his 42nd birthday.