Why?

just because the chinese shenzhou is taking a man into space doesn't mean they're soon going to have a space weaponry program. rather than that they will probably work on increasing accessibility to outer space than militarization of space. they will probably see an increase in military satelite technology but don't expect any goldeneye EMP weaponry anytime soon.

Unlike the majority of Chinese bright ideas this one has stayed in the local media day-to-day: so I think they are serious.
The publicly announced motives (and allow for my very feeble Mandarin) are two:
1) simply as a status thing -not unlike Kennedy's announcement about the Moon long ago. China very much wants to beat India or anyone else on this and sees it as one more step towards Olympics in 2008 (the biggest thing in China)
2) commercially: the Chinese see a window of opportunity here: they could offer commercial use at a fraction of Western rates.

China is - publicly at least - emphatically NOT weapons-oriented. The military gets little coverage and weapons-technology advances are seldom in the news.
Wher I live, it is possible to go to a high point ( the naval base itself is off-limits to foreigners) and actually see the hulk of China's aircraft carrier: they're not working on it.
China has better uses for money than weapons, at present.

yes unlike n. korea china is smarter in trying to build it's economy and provide for it's people rather than become madly militaristic.

Perhaps you should be more worried about a US space-weapons program, and Dunya's itchy trigger finger. Did you ever consider that maybe the Chinese just want to explore space? I think this is a good thing, as otherwise the Americans will remain entirely dominant in space.