Australia shares set to open lower after Wall St skid

SYDNEY, Dec 21 (Reuters) - Australian shares were set to start lower on Monday in the wake of steep falls on Wall Street and as prices for many of the country's major commodities remain under pressure despite a modest bounce in iron ore. The local share price index futures fell 0.8 percent to 5,021, an 85-point discount to the underlying S&P/ASX 200 index close of 5,106. The benchmark index had ended Friday with a slight gain after a very volatile week saw it fall to the lowest in two-an