Do I need a transit visa and clear customs in Beijing airport?

Hello,

I will be travelling to Hong Kong in May 2011. I will be flying on Air Canada from Toronto to Beijing and than have 1 hour 10 mts connecting time for my flight on China Airways to Hong Kong. Do i need a transit visa, also is 1 hour 10 mts enough time to catch my connecting flight to hong kong?. Do I need to clear chinese customs and collect my bags for re-check?..