Unfortunately I don't have many details, I was just informed by the agency that having a South African passport excluded me from getting a job as a pilot in China. I spoke to a collegue recently who worked in China and he told me the following story. True or not, I have no idea.
Just before the Beijing Olympics, there were 2 Cameroon nationals (that had terrorist links) that were caught with fake South African passports. China then placed South Africa on a 'blacklist' along with a few other countries and that since then it has been impossible for South Africans to get work permits there.
My research has turned up numerous relevant incidents but these are most relevant.
The countries listed are : Afghanistan, Tunisia, Algeria, Bangladesh , Congo, Egypt, Gambia, Ghana, Guinea, India, Indonesia, Iran, Iraq, Mali, Libya, South Africa, Morocco, Kazakhstan, Kirgizstan, Malaysia, Philippines, Uzbekistan, Tajikistan, Nepal, Pakistan, Nigeria, Sri Lanka, Sudan, Turkey, Mauritania, Saudi Arab, Sierra Leone, Syria.
Fake passports, IDs a 'crisis'
ISS Africa | Why al-Qa'eda Seems to Prefer South African Passports