Can I spread Human Ashes on the Great Wall of China?

Early April 2012 I am going to Beijing with my son and his daughter for 3 days. The reason is that my husband passed away 10months ago and it has always been his wish to visit the China Wall. It would have been our 40th wedding anniversay 8th April. I would like to know if I am able to take some of his "ashes" to spread when on the China Wall. I have spoken to NZ Customs and they say as long as I declare what I am carrying and have a copy of death certifcate. Can you please confirm to me.
Regards Helen