I have uploaded Category 6.x-2.0-alpha4 to my modules folder. When I try to install the module, something very odd is happening. The checkboxes for both Category and Category Menu are greyed out (cannot be selected) while Category Display and Category Re-Save (which are dependent on them) can be checked. Has anyone seen this before? Its like the logic behind which checkboxes are selectable has been reversed. None of my other modules are affected so I don't think this is a sitewide or drupal 6 issue. Any suggestions?