With apache 2.3.15 I had kinda the same issue with mod_fcgidon ubuntu 8.04 as on windows. With -k restart or -k graceful the server did not die like on windows, but the server delivered than only a 200 OK response header, but nothing more. Switching from worker mpm to event mpm seemed to solve this, but the server died later :-/
The bug 50309 is now longer than a year listet. Bad that none applied it yet.