Every time I try to edit a old posting, or create new one the list of categories is empty. I just debugged it and track it down to the following query, which returns Zero rows.
I checked the field authorid in ser_categories, and it is NULL.
SELECT c.*, a.username, a.realname FROM ser_category AS c LEFT OUTER JOIN ser_authors AS a ON c.authorid = a.authorid WHERE (c.authorid = 1 OR c.authorid = 0) ORDER BY category_name ASC
It seems to be a problem of upgrading from version 0.8 to 0.9. I just created new categories and in they have the authorid field set to a value, while the ones imported have it set to NULL.
I manually set the field to zero (all authors), and it is working now.