diff --git a/install.php b/install.php
index d7f0e962b7063a2e00f2d2af85f09cc8e7e13b16..e955cf0af047298c37cc58e9bbdd5ea4b9d15f2d 100644
--- a/install.php
+++ b/install.php
@@ -427,7 +427,8 @@ function check_functions(){
                          'file file_exists fseek flush filesize ftell fopen '.
                          'glob header ignore_user_abort ini_get mail mkdir '.
                          'ob_start opendir parse_ini_file readfile realpath '.
-                         'rename rmdir serialize session_start unlink usleep');
+                         'rename rmdir serialize session_start unlink usleep'.
+                         'preg_replace');
 
     if (!function_exists('mb_substr')) {
       $funcs[] = 'utf8_encode';