Given what he's done I certainly hope he's not crazy. A better question is whether creating deadly viruses is ethical.
EDIT: I should also note that I'm not judging whether what he's done is ethical (it's discussed at great length in the article) but if I had to take sides, I'm leaning towards being in favor of his work ... most research will have some degree of risk and in this case, I'm certain we'd rather not see another flu pandemic in the wild.