--- lib/Sendmail/PMilter.pm
+++ lib/Sendmail/PMilter.pm
@@ -925,6 +925,7 @@
 				undef $lsocket;
 				undef $@;
 				$SIG{PIPE} = 'IGNORE'; # so close_callback will be reached
+				$SIG{CHLD} = 'DEFAULT';
 				$SIG{$siginfo} = 'DEFAULT';
 
 				&$handler($socket);