* TSX up 2.44 points, or 0.02 percent to 12,602.18 * Materials off 0.27 percent, financials down 0.03 percent * Research In Motion surges 12.9 percent By Solarina Ho TORONTO, Jan 11 (Reuters) - Canada's main stock index rose slightly, but eked out enough of a gain to finish with its strongest close in 10 months, as a big rise in Research In Motion Ltd shares offset a decline in mining stocks. This was the fourth straight gain for the index and investors were looking ahead to