Dose a canadian citizen with canadian passport need the visa for 10 days travel from tehran to HK?

Dear Republic china Consulate in Tehran,

I am a Canadian with the Canadian passport and I'd rather travel for 10 days or less to Hong Kong participating in the China Sourcing Fair: Electronics & Components, October 12-15, 2011 in Hong Kong SAR. AsiaWorld -Expo. I have been registered by the the China Sourcing Fair and I have received my badge by post too but due to my job nature I am in Tehran now and I should depart from Tehran to HK. I wonder if I need the visa and if so what will be the requirements?

Best regards
A.Bernoos