diff -r ed812f1f7592 -r c752fdee555b src/hdalab/models/categories.py
--- a/src/hdalab/models/categories.py	Tue Mar 17 22:10:17 2015 +0100
+++ b/src/hdalab/models/categories.py	Wed Mar 18 18:52:43 2015 +0100
@@ -20,7 +20,7 @@
 class TagWpCategory(models.Model):
     tag = models.ForeignKey(Tag, related_name="wp_categories")
     wp_category = models.ForeignKey(WpCategory, related_name="tags")
-    hidden = models.BooleanField(blank=False, null=False)
+    hidden = models.BooleanField(blank=False, null=False, default=False)
     
     class Meta:
         app_label = 'hdalab'