Index: views/nodereferrer_view_handler_argument.inc
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/nodereferrer/views/nodereferrer_view_handler_argument.inc,v
retrieving revision 1.1.2.2
diff -u -p -r1.1.2.2 nodereferrer_view_handler_argument.inc
--- views/nodereferrer_view_handler_argument.inc	29 Oct 2009 18:04:00 -0000	1.1.2.2
+++ views/nodereferrer_view_handler_argument.inc	29 Nov 2009 19:24:44 -0000
@@ -93,6 +93,10 @@ class nodereferrer_view_handler_argument
     else {
       $in = '(' . implode(', ', $list) . ')';
 
+      if (!$this->options['operator']) {
+        $this->options['operator'] = 'in';
+      }
+
       $this->query->add_where(
         $this->options['group'],
         "$this->table_alias.$this->real_field " . $this->options['operator'] . ' ' . $in