Minor fix to return value.

db/Experiment.pm.in

@@ -963,7 +963,7 @@ sub AccessCheck($$$)
     my ($self, $user, $access_type) = @_;
 
     # Must be a real reference. 
-    return -1
+    return 0
 	if (! ref($self));
 
     if ($access_type < TB_EXPT_MIN ||