diff -r 1910d86afcbc -r 9eb810333b0f devtools/fill.py
--- a/devtools/fill.py	Tue Jan 21 14:56:06 2014 +0100
+++ b/devtools/fill.py	Wed Feb 12 18:15:32 2014 +0100
@@ -384,10 +384,10 @@
 
 def composite_relation(rschema):
     for obj in rschema.objects():
-        if obj.rdef(rschema, 'object').composite == 'subject':
+        if obj.rdef(rschema, 'object', takefirst=True).composite == 'subject':
             return True
     for obj in rschema.subjects():
-        if obj.rdef(rschema, 'subject').composite == 'object':
+        if obj.rdef(rschema, 'subject', takefirst=True).composite == 'object':
             return True
     return False