diff -r 0636c4960259 -r 3e7cad3967c5 server/sources/__init__.py
--- a/server/sources/__init__.py	Thu Jun 27 08:30:46 2013 +0200
+++ b/server/sources/__init__.py	Tue Jan 21 18:11:30 2014 +0100
@@ -64,9 +64,6 @@
 
 class AbstractSource(object):
     """an abstract class for sources"""
-    # does the source copy data into the system source, or is it a *true* source
-    # (i.e. entities are not stored physically here)
-    copy_based_source = False
 
     # boolean telling if modification hooks should be called when something is
     # modified in this source