diff --git a/bitbake/lib/bb/ui/crumbs/hoblistmodel.py b/bitbake/lib/bb/ui/crumbs/hoblistmodel.py
index b4d2a621b7..79e909c7f1 100644
--- a/bitbake/lib/bb/ui/crumbs/hoblistmodel.py
+++ b/bitbake/lib/bb/ui/crumbs/hoblistmodel.py
@@ -199,7 +199,9 @@ class PackageListModel(gtk.ListStore):
         return self.cmp_vals(val1, val2, user_data)
 
     def cmp_vals(self, val1, val2, user_data):
-        if val1.startswith(user_data) and not val2.startswith(user_data):
+        if val1 is None or val2 is None:
+            return 0
+        elif val1.startswith(user_data) and not val2.startswith(user_data):
             return -1
         elif not val1.startswith(user_data) and val2.startswith(user_data):
             return 1
@@ -575,7 +577,9 @@ class RecipeListModel(gtk.ListStore):
         return self.cmp_vals(val1, val2, user_data)
 
     def cmp_vals(self, val1, val2, user_data):
-        if val1.startswith(user_data) and not val2.startswith(user_data):
+        if val1 is None or val2 is None:
+            return 0
+        elif val1.startswith(user_data) and not val2.startswith(user_data):
             return -1
         elif not val1.startswith(user_data) and val2.startswith(user_data):
             return 1