Increasing Server Speed access from China - repost

Our server hosting a website builder application is situate in Hong Kong. Our customers from China found it very slow to upload db and info to their site builder from China. The tracing report from the customers' side in China showed that the ports at their side were very slow. This may be due to the China ISP, or the great China firewall. How can this problem be solved? We need advice and solution to solve this problem. Anyone got servers outside China which have no loading problems when accessing in China, but will also be fast when accessing in HK and in the US. We can also consider getting another server. Pls confirm you have experience of managing server outside China for access by customers in China when submitting your quotation, or otherwise, it will not be considered. Pls also confirm your quote include diagnosis of our server and providing an alternative dedicated server outside China and one year server hosting fee.