[CentOS] wait() fails

I have a program that forks a child, sleeps for a while
and then kills the child and waits for it.

On CentOs (4) the wait sometimes fails with a
"No child" error.  I have not seen this on any
other system.  This program has been
running for years on Solaris, older Redhat distributions, etc.
I would say the failure rate is about 1 in 10.

I put a breakpoint on the error and forced the
code to wait again. It works the second time.

Is this a known bug?

Mike