Hi Good Day to you!!!

I tried to call china embassy many times but no one answer the call.
My passport going to expire on 10 Oct 2011. I got my multiple entry visa on 3 Dec 2010 and it going to expire on 3 June 2011.I going China by 18 Apr 2011, understand that we need at least 6 months for travelling oversea.
Can my visa still can use?
Will China Custom acquire at least more than 6 months of our passport?
Appreciate for your advice.

thank you