--- C:\Documents and Settings\William\My Documents\plugins.py-orig 
+++ C:\Documents and Settings\William\My Documents\plugins.py-search 
@@ -25,6 +25,7 @@
 
 from zope.interface import implements
 import ldap
+from ldap import filter
 
 from repoze.who.interfaces import IAuthenticator, IMetadataProvider
 
@@ -76,7 +77,7 @@
         try:
             dn = self._get_dn(environ, identity)
             password = identity['password']
-        except (KeyError, TypeError, ValueError):
+        except (KeyError, TypeError, ValueError, IndexError):
             return None
 
         if not hasattr(self.ldap_connection, 'simple_bind_s'):
@@ -111,10 +112,24 @@
         @raise ValueError: If the C{login} key is not in the I{identity} dict.
         
         """
-        try:
-            return u'uid=%s,%s' % (identity['login'], self.base_dn)
-        except (KeyError, TypeError):
-            raise ValueError
+        #try:
+        #    return u'uid=%s,%s' % (identity['login'], self.base_dn)
+        #except (KeyError, TypeError):
+        #    raise ValueError
+        self.ldap_connection.simple_bind()
+        if '@' in identity['login']:
+            filters = filter.filter_format('(mail=%s)', (identity['login'],))
+        else:
+            filters = filter.filter_format('(uid=%s)', (identity['login'],))
+        environ['repoze.who.logger'].info('LDAP looking for: %s.' % filters)
+        results = self.ldap_connection.search_s(
+            self.base_dn,
+            ldap.SCOPE_SUBTREE,
+            filters,
+            ('dn',)
+        )
+        #self.ldap_connection.unbind()
+        return results[0][0]
 
     def __repr__(self):
         return '<%s %s>' % (self.__class__.__name__, id(self))