diff --git a/inc/auth/plain.class.php b/inc/auth/plain.class.php
index 319bdbe02ed07faf07f2b321811c4dd13778ca0f..02175d962c4330aa6531355441cabe5f52c523e3 100644
--- a/inc/auth/plain.class.php
+++ b/inc/auth/plain.class.php
@@ -310,8 +310,8 @@ class auth_plain extends auth_basic {
     function _constructPattern($filter) {
       $this->_pattern = array();
       foreach ($filter as $item => $pattern) {
-//        $this->_pattern[$item] = '/'.preg_quote($pattern,"/").'/';          // don't allow regex characters
-        $this->_pattern[$item] = '/'.str_replace('/','\/',$pattern).'/';    // allow regex characters
+//        $this->_pattern[$item] = '/'.preg_quote($pattern,"/").'/i';          // don't allow regex characters
+        $this->_pattern[$item] = '/'.str_replace('/','\/',$pattern).'/i';    // allow regex characters
       }
     }
 }