Signalhandler and "-ansi -pedantic -Wall"

Hi,

I've got a problem. I wrote a Program with a Signalhandler Routine. If i use
the compile flags "-ansi -pedantic -Wall", "(void) signal(SIGCHLD,Handler)"
catches the first signal but ignores the others. The installed handler
seems to be gone after the first run.
If I remove the "-ansi -pedantic -Wall" flags, everything works just fine.
But why?

thx a lot for your answers in advance !
.