diff --git a/scripts/builder/repository.py b/scripts/builder/repository.py
index f3f7d6f..7ea29bb 100644
--- a/scripts/builder/repository.py
+++ b/scripts/builder/repository.py
@@ -52,8 +52,8 @@ class Repository(object):
 class GitRepository(Repository):
 
 	def revision (self):
-		return repository.refs['HEAD']
-	
+		return self.repository.refs['HEAD']
+
 
 	def areTherePendingChanges (self):
 		return repository.is_dirty()