AT&T Corp says 1996 growth in consumer long distance business will be unlikely to match that for 1995, despite an aggressive marketing campaign. Analysts say it’s partly because of competition from new entrants to the market. The consumer market is far more problematic than we expected, with competition not just from MCI Communications Corp and Sprint Corp but from newer carriers like Excel Communications Inc, said Richard Klugman of PaineWebber Inc. All of which means that the company will be putting even more effort into winning business in foreign markets.