As a member live in China, I can provided some personal comments regarding ship the cutting to overseas/receive the cutting from overseas.
1. I do agree with Jon's point that it is illegal for any foreign country to import cuttings without an import permit and a phytosanitary certificate. But that's really difficult for a person to apply an import permit individually in China, the most workable way would be to find a agent company to settle it, but it would cost hundreds of USD for 1 shipment(part of money is paid for the permit & part of money is paid for the agent fee). If it's just a personal hobby, it really cost too much. So most of time, we choose to do something "illegally".
2. The worst situation for us would be - the package inspected by customs & get destroyed, the only loss for us is the cutting cost & shipping cost, no extra penalty from customs.
3. I used to received a package from USA which was inspected by US customs, so it seems that there is no restriction for the cuttings export from US to overseas.
4. I've sent out several packages this year to France, USA & Canada with no issue, some of them even was not the cuttings but the little trees. So I have to say the general inspection rate won't be quite high & most of us would be the lucky guy.
So, we can see that most of ebay seller would indicate it as - it should be buyer's responsibility to understand their country's law for the importation, that would be treated as a term of the deal.