CALCUTTA'S corporate grapevine is abuzz with rumours that Manu Chhabria may be selling his troubled crown jewel, Shaw Wallace. The buyer is reportedly the Canadian liquor and entertainment giant, Seagram. The company made a bid for Shaw Wallace in 1984-85 but Chhabria grabbed the company by offering a higher price. Although Chhabria denied any intention of selling Shaw Wallace, a source close to Seagram, while denying that any deal had been struck, is unwilling to say if such a deal would not be struck in the future.