diff --git a/Products/LDAPMultiPlugins/LDAPPluginBase.py b/Products/LDAPMultiPlugins/LDAPPluginBase.py
index 62971ab..9f3a290 100644
--- a/Products/LDAPMultiPlugins/LDAPPluginBase.py
+++ b/Products/LDAPMultiPlugins/LDAPPluginBase.py
@@ -81,7 +81,13 @@ class LDAPPluginBase(Folder, BasePlugin, Cacheable):
         if not acl or not login or not password:
             return None, None
 
-        user = acl.getUser(login, pwd=password)
+        try:
+            user = acl.getUser(login, pwd=password)
+        except IndexError:
+            # workaround bug in Products.LDAPUserFolder that happens when the
+            # login is an accentuated variant of an existing login and the
+            # password is correct :/
+            return None, None
 
         if user is None:
             return None, None