diff --git a/fhem/FHEM/91_watchdog.pm b/fhem/FHEM/91_watchdog.pm
index 3eb9e1552..cfac40ba4 100755
--- a/fhem/FHEM/91_watchdog.pm
+++ b/fhem/FHEM/91_watchdog.pm
@@ -69,6 +69,11 @@ watchdog_Define($$)
 
   }
 
+  InternalTimer(1, sub($){
+    my $re = ($re1 eq "." ? "" : $re1)."|".($re2 eq "SAME" ? $re1 : $re2);
+    notifyRegexpChanged($watchdog, $re);
+  }, $watchdog, 0);
+
   return undef;
 }