diff --git a/fhem/fhem.pl b/fhem/fhem.pl
index 71475aac4..de9e7ba0d 100755
--- a/fhem/fhem.pl
+++ b/fhem/fhem.pl
@@ -2775,7 +2775,7 @@ HandleTimeout()
 
 #####################################
 sub
-InternalTimer($$$$)
+InternalTimer($$$;$)
 {
   my ($tim, $fn, $arg, $waitIfInitNotDone) = @_;