The Dow Jones industrial average posted its biggest gain in day since 2002 to end at 13,862 - up 284 points. The Nasdaq soared 50 points to 2702.Indian ADRs, too, ended with smart gains. Patni Computers, ICICI Bank, HDFC Bank and VSNL soared over 4% each to $25.78, $52.42, $91.55 and $24.20, respectively. Satyam, Tata Motors and Dr.Reddy's are the other major gainers.