[Product-Developers] objects not saved in bin/instance run script

[Maxfield]

 	Appreciate any help with this, I have a feeling I'm missing
 	some kind of unknown magic in here. I'm trying to add a
 	new MutablePropertySheet to a MembraneUser...


---------begin----------------------------------
from Testing import makerequest
import transaction
from Products.CMFCore.utils import getToolByName
from Products.PlonePAS.sheet import MutablePropertySheet
from AccessControl.SecurityManagement import newSecurityManager
from AccessControl.User import system
from Acquisition import aq_base

import pdb

objs = app.listDAVObjects()

#
# find the plone site
#
plone_site = None
for o in objs:
     if o.__class__.__name__ is 'PloneSite':
         plone_site = o

app = makerequest.makerequest(app)
newSecurityManager(None,system)

MYPROPSHEET = 'remote_properties'
MYPROPTYPE = 'lines'
MYPROPNAME = 'messages'

acl_users =  getToolByName(plone_site,'acl_users')
howard = acl_users.getUserById('howard')
psheets = howard.listPropertysheets()

print psheets

if MYPROPSHEET in psheets:
     print 'found propertysheet'
else:
     print 'could not find "' + MYPROPSHEET + '" in propertysheets'
     try:
         new_sheet = MutablePropertySheet( MYPROPSHEET, [ ( MYPROPNAME, 'lines' ) ]  )
         howard.addPropertysheet( MYPROPSHEET, new_sheet )
     except KeyError:
         print 'property sheet could not be found but also could not be added!'
         sys.exit(1)

transaction.commit()
----------------end----------------------------