prevent Traceback in dataforms_widget(search user in jabber.tf-network.de server as example)

src/dataforms_widget.py

@@ -193,8 +193,9 @@ class DataFormWidget(gtk.Alignment, object):
         for item in self._data_form.iter_records():
             iter_ = self.multiplemodel.append()
             for field in item.iter_fields():
-                self.multiplemodel.set_value(iter_, fieldvars.index(field.var),
-                        field.value)
+                if field.var in fieldvars:
+                    self.multiplemodel.set_value(iter_,
+                        fieldvars.index(field.var), field.value)
 
         # constructing columns...
         for field, counter in zip(self._data_form.reported.iter_fields(),