Problem to solve:
Visiting China for a short period of time, and GPRS is critically important.
After you arrive in China (don’t need to worry about it. There are soooo many sellers about the SIM card at airport or at hotel), get a Shenzhouxing pre-paid SIM card from China Mobile. With the card, you have immediate access of GPRS (nothing is needed). However, be very cautious that the default plan is very expensive.
Check the GPRS Package from China Mobile, and choose one that is good for you. I would recommend the 20 RMB for 50M traffic plan. Then call 10086 and ask the operator to adopt the plan for you.
Then enjoy your GPRS!