--- a/server/sources/__init__.py	Thu Apr 21 16:33:55 2011 +0200
+++ b/server/sources/__init__.py	Thu Apr 21 12:35:41 2011 +0200
@@ -139,11 +139,11 @@
             return -1
         return cmp(self.uri, other.uri)
 
-    def backup(self, backupfile, confirm):
+    def backup(self, backupfile, confirm, format='native'):
         """method called to create a backup of source's data"""
         pass
 
-    def restore(self, backupfile, confirm, drop):
+    def restore(self, backupfile, confirm, drop, format='native'):
         """method called to restore a backup of source's data"""
         pass