--- a/misc/migration/3.5.3_Any.py	Wed Oct 07 23:17:32 2009 +0200
+++ b/misc/migration/3.5.3_Any.py	Wed Oct 07 23:20:01 2009 +0200
@@ -1,4 +1,7 @@
-sync_schema_props_perms('state_of')
-sync_schema_props_perms('transition_of')
-
-add_attribute('BaseTransition', 'type')
+# type attribute might already be there if migrating from
+# version < 3.5 to version >= 3.5.3, BaseTransition being added
+# in bootstrap_migration
+if versions_map['cubicweb'][0] < (3, 5, 0):
+    add_attribute('BaseTransition', 'type')
+    sync_schema_props_perms('state_of')
+    sync_schema_props_perms('transition_of')