While looking at
MDL-17369, I came across the following PHP warning:
Warning: max() [function.max]: Array must contain at least one element in /home/arborrow/Moodle/code/cvshead/mod/forum/lib.php on line 3584
Attached is a patch file based on HEAD but could easily be applied to 1.9. Essentially I am just moving things around to avoid calling max if there are no ratings yet. Let me know if there are any questions.
Peace - Anthony