Lamas, 24, was seen approaching the bash but did not enter; Dailymail.com sources said the invitation noted that the guest list would be strictly enforced.
The Hot Right Now songstress, 32, showed off her perky chest in a black satin minidress on Saturday night as she attended Leonardo Di Caprio s 49th birthday party in Beverly Hills.
The Titanic actor, who just turned 49, and Naomi, 53, were widely reported to have had a fling back in 1995 - before going on to become good friends, and still remain as such nowadays.
Hollywood star Leonardo DiCaprio celebrated his 49th birthday in style over the weekend with a glittering guestlist that saw his former flame turned away at the door