Sorting in 'Filter Results' gadget for Project does not work correctly

The project name does not seems to be taken into consideration when trying to sort it by clicking on the column title.

Steps to reproduce

1. Create a project named
   • Demonstration Project
   • 00 Percubaan
   • 10 Percubaan
   • 15 Percubaan
2. Create issues on each of the projects
3. Add 'Filter Results' gadget
4. Add filter of all 4 projects
5. Click on the 'Project' title column to sort

The result from JIRA 5.2.11

Expected results

The result from JIRA 6.0.4