New York real estate tycoon Donald Trump says half-seriously that he wishes media mogul Rupert Murdoch hadn't sold the New York Post. "Rupert, come back!" Trump implored Thursday at a breakfast at the Republican National Convention in New Orleans. Trump accused new Post publisher Peter Kalikow of picking on him in the newspaper at the same time Kalikow persuaded him to buy advertising for a department store chain Trump controls. "You son of a gun, you're killing me," said Trump, who related that a Post reporter called him about the same time as the advertising request to ask whether the stores were closing. "You don't know how devastating that is to employee morale" to see stories like that in the paper, Trump said. Kalikow, who bought the financially ailing paper in March, was sitting a few feet away in the audience. Trump sounded at least half-serious, and while Kalikow was laughing, he looked uncomfortable.