My man page says sigwait never returns an error, but I'm definately seeing a nonzero return in my application. I have taken a solid crack at duplicating it in a test case without succes, I'd be happy to try more if someone sends me an email telling me I'm not wasting my time on a known issue. Bugzilla didn't show anything for a search on 'sigwait'.
I'm closing this bug because there is no specific in there at all. There used to be a bug a long time ago where sigwait sometimes returned EINTR. But this is fix since 2005-8-1.