Well i got ph for 9100 and battery is 960mah ... I talked continuously for around 4 hours(courtesy reliance Re 1 per 3 min) and still phone remained awake for another 12 hours.....
The only problem is it takes almost 4 hours to charge. Although after 1.5-2 hrs we can see all 5 bars if I remove it from charger but inorder to get the Battery is Full message u hveta charge is for at least 3-4 hrs .