That this virus first appeared in Asia (likely China) is evidence of nothing. Most of these new human-transmittable viruses appear in Asia because that's where you find hundreds of millions of people living next to pigs and other animals, often in extremely unsanitary conditions.

And those conditions are what make the jump to human transmission possible.

Obviously this is not evidence against SARS being a bioweapon, but it is a refutation of the only piece of evidence that Charlie cites.