Here is in part why the EVA Suit performance is critical and a new item:

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China has offered little clues about its systems for spacewalking. The in-flight pressure suits worn by Shenzhou astronauts have been extensively documented and exhibited. The similarities to the Sokol spacesuits worn by Russian Soyuz crewmembers are striking. China is known to have derived much inspiration from the Russian space program, so it's reasonably to suspect that their extravehicular spacesuits have been influenced by Russia's Orlan suits. Modifications could be made to allow the suit to pass through the hatch in Shenzhou's Orbital Module.

But China could still be blazing a new trail, as far as comparisons to Soyuz are concerned. Extravehicular activities performed directly from Russian Soyuz spacecraft are rare, and none have been attempted using a modern Orlan suit. In 1968, Soyuz 4 and 5 docked in orbit. Two crewmembers spacewalked from one Soyuz to the other.
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The rest is http://en.chinabroadcast.cn/811/2006/02/15/199@51188.htm