Here is a link to a a discussion on the evolution mailing list, where a user cofirms on same version and another user says it does not affect previous version. Perhaps this helps to narrow down cause.
http://www.listware.net/201007/evolution-list/54596-evolution-cannot-create-new-or-delete-existing-categories.html -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org