diff -r 00fc169cc6a9 -r 0a1744477bc1 web/hdalab/models/categories.py
--- a/web/hdalab/models/categories.py	Fri Jun 22 19:16:46 2012 +0200
+++ b/web/hdalab/models/categories.py	Mon Jul 02 19:19:02 2012 +0200
@@ -44,3 +44,13 @@
     class Meta:
         app_label = 'hdalab'
         unique_together = ('tag_infobox','param_name')
+
+# Added on 02/07/2012
+
+class WpCategoryInclusion(models.Model):
+    parent_category = models.ForeignKey(WpCategory, related_name="child_categories")
+    child_category = models.ForeignKey(WpCategory, related_name="parent_categories")
+    
+    class Meta:
+        app_label = 'hdalab'
+        unique_together = ('parent_category','child_category')
\ No newline at end of file