Gradebook

After sort the grades with something, everytime change the groups, I must click the sort link again, ..........So, I made this little patch:

diff -r1.16.2.12 lib.php
134a135
>     global $group;
2811c2820
<         $url = 'index.php?id='.$course->id;
---
>         $url = 'index.php?id='.$course->id.'&amp;sort='.optional_param('sort','default');