diff --git a/pandora_server/ChangeLog b/pandora_server/ChangeLog
index 97cd5ac3c5..2e73ceea85 100644
--- a/pandora_server/ChangeLog
+++ b/pandora_server/ChangeLog
@@ -1,3 +1,7 @@
+2014-05-25  Junichi Satoh <junichi@rworks.jp>
+
+	* lib/PandoraFMS/Tools.pm: Fixed STD* file open error.
+
 2014-05-22  Ramon Novoa  <rnovoa@artica.es>
 
 	* lib/PandoraFMS/NetworkServer.pm,
diff --git a/pandora_server/lib/PandoraFMS/Tools.pm b/pandora_server/lib/PandoraFMS/Tools.pm
index 35e344a626..f0b75b350e 100644
--- a/pandora_server/lib/PandoraFMS/Tools.pm
+++ b/pandora_server/lib/PandoraFMS/Tools.pm
@@ -254,9 +254,9 @@ sub ascii_to_html($) {
 
 sub pandora_daemonize {
 	my $pa_config = $_[0];
-	open STDIN, '$DEVNULL'		or die "Can't read $DEVNULL: $!";
-	open STDOUT, '>>$DEVNULL'	or die "Can't write to $DEVNULL: $!";
-	open STDERR, '>>$DEVNULL'	or die "Can't write to $DEVNULL: $!";
+	open STDIN, "$DEVNULL"		or die "Can't read $DEVNULL: $!";
+	open STDOUT, ">>$DEVNULL"	or die "Can't write to $DEVNULL: $!";
+	open STDERR, ">>$DEVNULL"	or die "Can't write to $DEVNULL: $!";
 	chdir '/tmp'					or die "Can't chdir to /tmp: $!";
 	defined(my $pid = fork)		or die "Can't fork: $!";
 	exit if $pid;