Kevin,
My mate in Brizzie called the Chinese Embassy in Canberra and was told the following:-

1) Take your original degree to a 'Notary Public' (a bit like a JP but with a bigger dick!). The NP will verify it is genuine.
2) Take the signed degree to the Dept of Foreign Trade. They will verify that the signature actually BELONGS to a person with such a big dick.
3) Take the twice-signed degree to the Chinese embassy who will verify that the DFT signature actually belongs to someone at the DFT, and not your Mum!

That's it! Easy! The whole process shouldn't cost you more than around AUD$700 - AUD$800.

Of course, you could always choose option B, which is-

TELL CHINA TO HAVE SEX AND TRAVEL AND THEN GO AND WORK IN A COUNTRY THAT DOESN'T REQUIRE THIS LEVEL OF UNNECESSARY BULLSHIT!