diff --git a/plugins/kolab_auth/kolab_auth_ldap.php b/plugins/kolab_auth/kolab_auth_ldap.php
index ddf7cffe..d529b73e 100644
--- a/plugins/kolab_auth/kolab_auth_ldap.php
+++ b/plugins/kolab_auth/kolab_auth_ldap.php
@@ -329,12 +329,14 @@ class kolab_auth_ldap extends rcube_ldap_generic
 
         // fields mapping
         foreach ($this->fieldmap as $field => $attr) {
-            // $entry is indexed by lower-case attribute names
+            // $entry might be indexed by lower-case attribute names
             $attr_lc = strtolower($attr);
             if (isset($entry[$attr_lc])) {
                 $entry[$field] = $entry[$attr_lc];
             }
-            // @TODO: consider returning also $entry[$attr] when $attr != $attr_lc
+            else if (isset($entry[$attr])) {
+                $entry[$field] = $entry[$attr];
+            }
         }
 
         return $entry;