[eluser]Phil Sturgeon[/eluser]
That is very strange. I changed the field from parent to parent_id a while back to make it more standard and could have sworn I listed the change in the UPGRADE file. It has now been added, sorry about that.
The forum module is... kinda done. Needs the views cleaned, language strings added and some little tweaks here and there. You can grab the code from the "forums" branch on GitHub if you want to give it a spin.
