Greece's prime minister promised Wednesday to hold safe and successful Olympics despite "choking deadlines" in construction and admissions by his ministers of delays in security preparations at two key sites. "Not a single hour can be wasted," Premier Costas Caramanlis said in an interview with a magazine issued by organizers of the Aug. 13-29 Games. "Everyone knows that four months before the Olympic Games we are facing chocking deadlines." But he added: "I want to be clear, our main concern and highest priority in Olympic preparations is to secure the complete safety of the country, of athletes and visitors ......