diff --git a/organize/README.txt b/organize/README.txt
index 68b8f8b..a97a541 100644
--- a/organize/README.txt
+++ b/organize/README.txt
@@ -33,8 +33,9 @@ ZCML setup):
   >>> person = concepts['person']
 
   >>> from loops.concept import Concept
-  >>> johnC = concepts['john'] = Concept(u'John')
-  >>> johnC.conceptType = person
+  >>> from loops.setup import addAndConfigureObject
+  >>> johnC = addAndConfigureObject(concepts, Concept, 'john', title=u'John',
+  ...                               conceptType=person)
 
 
 Organizations: Persons (and Users), Institutions, Addresses...
@@ -237,6 +238,18 @@ The person-based authenticator provides authentication without having to
 store a persistent (internal) principal object.
 
   >>> from loops.organize.auth import PersonBasedAuthenticator
+  >>> pbAuth = PersonBasedAuthenticator('persons.')
+  >>> pau['persons'] = pbAuth
+  >>> pau.authenticatorPlugins = ('loops', 'persons',)
+
+  >>> eddieC = addAndConfigureObject(concepts, Concept, 'eddie', title=u'Eddie',
+  ...                                conceptType=person)
+  >>> eddie = adapted(eddieC)
+  >>> eddie.userId = 'persons.eddie'
+
+  >>> pbAuth.setPassword('eddie', 'secret')
+  >>> pbAuth.authenticateCredentials(dict(login='eddie', password='secret'))
+  PrincipalInfo(u'persons.eddie')
 
 
 Security
@@ -332,7 +345,6 @@ Tasks and Events
 Task view with edit action
 --------------------------
 
-  >>> from loops.setup import addAndConfigureObject
   >>> from loops.organize.interfaces import ITask
   >>> task = addAndConfigureObject(concepts, Concept, 'task', title=u'Task',
   ...                              conceptType=type, typeInterface=ITask)
@@ -399,7 +411,7 @@ Send Email to Members
   >>> form.subject
   u"loops Notification from '$site'"
   >>> form.mailBody
-  u'\n\nEvent #1\nhttp://127.0.0.1/loops/views/menu/.target95\n\n'
+  u'\n\nEvent #1\nhttp://127.0.0.1/loops/views/menu/.target97\n\n'
 
 
 Fin de partie
diff --git a/organize/auth.py b/organize/auth.py
index c87c677..fa50f01 100644
--- a/organize/auth.py
+++ b/organize/auth.py
@@ -25,17 +25,34 @@ $Id$
 from persistent import Persistent
 from zope.app.container.contained import Contained
 from zope import component
-from zope.interface import implements
+from zope.interface import Interface, implements
 from zope.app.authentication.interfaces import IAuthenticatorPlugin
 from zope.app.authentication.principalfolder import PrincipalInfo
 from zope.app.principalannotation.interfaces import IPrincipalAnnotationUtility
 from zope.app.security.interfaces import IAuthentication
-from zope.cachedescriptors.property import Lazy
+from zope import schema
+from zope.traversing.api import getParent
+
+from loops.util import _
+
+
+class IPersonBasedAuthenticator(Interface):
+
+    prefix = schema.TextLine(
+        title=_("Prefix"),
+        description=_(
+        "Prefix to be added to all principal ids to assure "
+        "that all ids are unique within the authentication service"),
+        missing_value=u"",
+        default=u'',
+        readonly=True)
 
 
 class PersonBasedAuthenticator(Persistent, Contained):
 
-    implements(IAuthenticatorPlugin)
+    implements(IAuthenticatorPlugin, IPersonBasedAuthenticator)
+
+    passwordKey = 'loops.organize.password'
 
     def __init__(self, prefix=''):
         self.prefix = unicode(prefix)
@@ -45,11 +62,8 @@ class PersonBasedAuthenticator(Persistent, Contained):
             return None
         login = credentials.get('login')
         password = credentials.get('password')
-        if not login or not password :
-            return None
-        id = self.prefix + login
-        if self._checkPassword(id, password):
-            return PrincipalInfo(id, login, login, u'')
+        if self.checkPassword(login, password):
+            return PrincipalInfo(self.prefix + login, login, login, u'')
         return None
 
     def principalInfo(self, id):
@@ -58,19 +72,35 @@ class PersonBasedAuthenticator(Persistent, Contained):
             if login:
                 return PrincipalInfo(id, login, login, u'')
 
+    def checkPassword(self, login, password):
+        if login and password:
+            pa = self.getPrincipalAnnotations(
+                        getParent(self).prefix + self.prefix + login)
+            return pa.get(self.passwordKey) == password
+        return None
+
     def setPassword(self, login, password):
-        id = self.prefix + login
-        pa = self.getPrincipalAnnotations(id)
-        pa['loops.organize.password'] = password
+        pa = self.getPrincipalAnnotations(
+                        getParent(self).prefix + self.prefix + login)
+        pa[self.passwordKey] = password
 
-    @Lazy
-    def principalAnnotations(self):
-        return component.getUtility(IPrincipalAnnotationUtility)
+    def getPrincipalAnnotations(self, id):
+        utility = component.getUtility(IPrincipalAnnotationUtility)
+        return utility.getAnnotationsById(id)
 
-    def getPrincipalAnnotations(id):
-        return self.principalAnnotations.getAnnotationsById(id)
+    def get(self, login):
+        return InternalPrincipal(self, login)
 
-    def _checkPassword(self, id, password):
-        pa = self.getPrincipalAnnotations(id)
-        return pa.get('loops.organize.password') == password
+
+class InternalPrincipal(object):
+
+    def __init__(self, auth, login):
+        self.auth = auth
+        self.login = login
+
+    def checkPassword(self, password):
+        return self.auth.checkPassword(self.login, password)
+
+    def setPassword(self, passowrd):
+        self.auth.setPassword(self.login, password)
 
diff --git a/organize/browser/configure.zcml b/organize/browser/configure.zcml
index c602c89..2162574 100644
--- a/organize/browser/configure.zcml
+++ b/organize/browser/configure.zcml
@@ -62,4 +62,30 @@
       class="loops.organize.browser.party.SendEmailForm"
       permission="zope.View" />
 
+  <!-- authentication -->
+
+  <browser:addform
+      schema="loops.organize.auth.IPersonBasedAuthenticator"
+      label="Add Person-based Authenticator"
+      content_factory="loops.organize.auth.PersonBasedAuthenticator"
+      keyword_arguments="prefix"
+      name="AddPersonBasedAuthenticator.html"
+      permission="zope.ManageServices"
+      />
+
+  <browser:addMenuItem
+      title="Person-based Authenticator"
+      description="An authentication plugin for loops Persons"
+      class="loops.organize.auth.PersonBasedAuthenticator"
+      permission="zope.ManageServices"
+      view="AddPersonBasedAuthenticator.html" />
+
+  <browser:schemadisplay
+      schema="loops.organize.auth.IPersonBasedAuthenticator"
+      label="Authenticator Prefix"
+      name="prefix.html"
+      fields="prefix"
+      permission="zope.ManageServices"
+      menu="zmi_views" title="Prefix" />
+
 </configure>
diff --git a/organize/configure.zcml b/organize/configure.zcml
index 1508e5f..2a6c454 100644
--- a/organize/configure.zcml
+++ b/organize/configure.zcml
@@ -48,6 +48,14 @@
              interface="loops.organize.interfaces.IMemberRegistrationManager" />
   </zope:class>
 
+  <!-- authentication -->
+
+  <zope:localUtility class="loops.organize.auth.PersonBasedAuthenticator">
+    <require
+        permission="zope.ManageServices"
+        attributes="prefix" />
+  </zope:localUtility>
+
   <!-- other adapters -->
 
   <zope:adapter factory="loops.organize.schema.PersonSchemaFactory" />