* TSX up 3.82 points, or 0.03 percent, at 12,820.45 * Six of the 10 main sectors higher * RIM shares off 2.6 pct ahead of BlackBerry 10 launch By Solarina Ho TORONTO, Jan 28 (Reuters) - Canada's main stock index pared early gains to trade little changed at midmorning on Monday, as firmer bank stocks were offset by weaker Research In Motion Ltd shares and falling natural resource stocks. Investors were positioning ahead of the RIM's critical launch of its new BlackBerry 10