diff --git a/src/pfwbged/collection/searchview.py b/src/pfwbged/collection/searchview.py
index 4549e5e..dbd291c 100644
--- a/src/pfwbged/collection/searchview.py
+++ b/src/pfwbged/collection/searchview.py
@@ -27,6 +27,7 @@ from plone.z3cform.layout import wrap_form
 import plone.app.querystring.querybuilder
 from plone.app.querystring.interfaces import IQuerystringRegistryReader
 from plone.registry.interfaces import IRegistry
++from plone.app.contentlisting.contentlisting import ContentListing
 
 from pfwbged.collection import _
 
@@ -389,6 +390,14 @@ class ContentListingView(BrowserView):
 
 
 class QueryBuilder(plone.app.querystring.querybuilder.QueryBuilder):
+    def _makequery(self, *args, **kwargs):
+        results = plone.app.querystring.querybuilder.QueryBuilder._makequery(self, *args, **kwargs)
+        if isinstance(results, ContentListing):
+            # results may have been padded with None, but ContentListing
+            # doesn't like that.
+            results._basesequence = [x for x in results._basesequence if x is not None]
+        return results
+
     def html_results(self, query):
         """html results, used for in the edit screen of a collection,
            used in the live update results"""