Pershing Square Capital Management LP, a hedge fund run by activist investor William Ackman, has purchased a roughly 2 percent stake in Kraft Foods Inc. Kraft said Ackman supports its bid to acquire British candy maker Cadbury PLC but is urging it to limit the stock component of the more than $16 billion stock-and-cash offer. Kraft, maker of Oreo cookies and Nabisco crackers, said Friday that Ackman's investment is a sign of "great confidence" in the company's management and prospects. Ackman could not immediately be reached for comment. He was the second major U.S. investor to weigh in on Kraft's campaign to buy Cadbury, the maker of Dairy Milk candy bars and Dentyne gum. Berkshire Hathaway, managed by billionaire Warren Buffett and Kraft's largest shareholder, also warned against using more shares to accomplish the deal.