Index: lib/extended_queries_helper_patch.rb
===================================================================
--- lib/extended_queries_helper_patch.rb	(Revision 117)
+++ lib/extended_queries_helper_patch.rb	(Arbeitskopie)
@@ -23,6 +23,9 @@
 
                 if !column.custom_field.respond_to?(:visible_by?) || column.custom_field.visible_by?(issue.project, User.current)
                     value = issue.custom_field_values.detect{ |value| value.custom_field_id == column.custom_field.id }
+                    if value.nil?
+                        return nil
+                    end
 
                     h(show_value(value))
                 else