While the Chinese government is far too punitive and vindictive, I think that their punishment here is right on. The former head of their FDA just got hammer-dunked as a result of accepting nearly $1 million in bribes to let drugs get approved in China. Death is a bit much in most bribery cases, but as people died because of his negligence, I don't have a problem with it. In this case the punishment fits the crime. Working in favor of Zheng is that the Chinese justice system is rather swift, and as a result, he won't be subject to any Jack Bauer-esque stints in a Chinese prison.
I really think that bribery cases like this should be subject to stiffer fines here in the US. Sure, there is the ever-popular trip to Club Fed as an option, but why not a fine equal to the amount that you were bribed? In almost every bribery case that this would apply to, the public official wouldn't be able to pay back the money and that's not a bad thing. They'd hit bankruptcy and that's a nice little disincentive. Of course, the Dukestir got hit with something that was pretty harsh, but he's more the exception than the rule. Let's get a little punitive when people are putting us in danger or wasting our tax dollars (well, wasting them as a result of a bribe - if it was just wasting our money in general, we'd end up without a Congress half way through their terms).