diff -r d3016c08b4ae -r a2a0bc984863 server/querier.py
--- a/server/querier.py	Wed Jan 22 12:14:56 2014 +0100
+++ b/server/querier.py	Tue Jul 02 17:07:34 2013 +0200
@@ -516,7 +516,7 @@
         self.solutions = repo.vreg.solutions
         rqlhelper = repo.vreg.rqlhelper
         # set backend on the rql helper, will be used for function checking
-        rqlhelper.backend = repo.config.sources()['system']['db-driver']
+        rqlhelper.backend = repo.config.system_source_config['db-driver']
         self._parse = rqlhelper.parse
         self._annotate = rqlhelper.annotate
         # rql planner