--- a/server/session.py	Tue Mar 30 11:15:57 2010 +0200
+++ b/server/session.py	Tue Mar 30 11:17:21 2010 +0200
@@ -28,6 +28,11 @@
 
 NO_UNDO_TYPES = schema.SCHEMA_TYPES.copy()
 NO_UNDO_TYPES.add('CWCache')
+# is / is_instance_of are usually added by sql hooks except when using
+# dataimport.NoHookRQLObjectStore, and we don't want to record them
+# anyway in the later case
+NO_UNDO_TYPES.add('is')
+NO_UNDO_TYPES.add('is_instance_of')
 # XXX rememberme,forgotpwd,apycot,vcsfile
 
 def is_final(rqlst, variable, args):