We're sorry, Ms. (Janet) Jackson, but celebrity fashion lines are usually a wardrobe malfunction of the highest order: throw a star and a bunch of fancy garms together, and hope gawping sleb-sessed punters will part with cash on dubious trends. Yet André 3000 (née Benjamin) of OutKast holds a little more credibility. Over the years he's furrowed an idiosyncratic line in Thirties dandy-wear and collegiate apparel. His new Benjamin Bixby label, launched at a lavish......