China Unicom is set to launch Apple’s iPhone 4 on the mainland September 16, a source from China Unicom told “Caixin Online” (http://macosg.me/2/rf).

According to the source, customers that want to buy the iPhone4 from China Unicom will need to order the phone online ahead of the launch date. China Unicom, the exclusive provider of iPhone in China, launched the 8G version of the iPhone 3GS on Aug. 9.

“Caixin Online” says the iPhone 4 is expected to suffer from the same issues related to signal reception in China. However, China Unicom will be offering iPhone cases to customers as a free gift.