Fidel Castro told thousands of admirers he wasn't well enough to join them to launch the delayed five-day celebration of his 80th birthday, raising new questions about the health of the ailing Cuban leader. The message from Castro, which was read to a crowd of 5,000 at the Karl Marx Theater and on state TV, indicates that he is far from recovered from a mysterious ailment that forced him on July 31 to turn over power to his brother, Defense Minister Raul Castro. The Cuban leader turned 80 on August 13 but delayed his birthday celebrations as he recovered from surgery two weeks earlier for intestinal bleeding. "I direct myself to you, intellectuals and prestigious personalities of the world, with a dilemma," said Castro's note. "I could not meet with you in a small locale, only in the Karl Marx Theater where all the visitors would fit, and I was not yet in condition, according to the doctors, to face such a colossal encounter." "My very close friends, who have done me the honor of visiting our country, I sign off with the great pain of not having been able to personally give thanks and hugs to each and every one of you," Castro wrote. The crowd responded with a standing ovation.