By Josh Ong

Published: 08:50 PM EST (05:50 PM PST)

Apple is attempting to block scalpers by instituting new restrictions preventing walk-in sales of the iPhone at Apple Stores in China. Customers must first reserve an iPhone on Apple's website before visiting an Apple Retail Store to complete the purchase.

The new policies, which were posted on the Apple China site (Google Translation), require customers to make an online booking for the iPhone 4 and iPhone 3GS and schedule a day and time to pick it up.

According to MIC Gadget, the name on the customer's ID must exactly match the name on the purchase order when the iPhone is picked up. Each customer is allowed only one iPhone purchase per day.

Scalpers in Beijing and Shanghai have been taking advantage of the limited supply of the iPhone 4 by selling stacks of marked-up iPhones outside Apple retail stores. At one point, customers had become so fed up with the scalpers, who wait in line to snatch up new shipments of the smartphone as quickly as possible, that a fight broke out at a Beijing Apple Store. Apple security and local police had to close the store in order to defuse the situation.

Despite the iPhone 4 being available on China's grey market since shortly after the U.S. launch in June, Chinese demand for the iPhone 4 has been stronger than expected. Thousands of buyers lined up outside Apple's 4 retail stores in China to buy the iPhone 4 on launch day, Sept. 25.

It may take more than a month for Apple to catch up to heavy demand for the iPhone 4 in China. China Unicom received over 200,000 pre-orders before the release of the handset, but the carrier was only able to fulfill half of the orders in the first few days of availability. China's second-largest carrier warned that some customers who pre-ordered the device might have to wait until late October to receive the device.

Even as Apple enjoys increased interest in the iPhone 4 through its partnership with China Unicom, the Cupertino, Calif., company could be looking to expand to other carriers in China. Analysts speculated earlier this week that China Telecom is in negotiations with Apple over a CDMA iPhone that could be released in early 2011.

China Mobile, the world's largest cellular provider with over 570 million subscribers, reached out to Apple earlier this year to request an iPhone compatible with the carrier's proprietary TD-SCDMA 3G standard.