diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 051ee4022b0..4713542bf5b 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -1169,23 +1169,34 @@ function dol_sanitizeUrl($stringtoclean, $type = 1)
  */
 function dol_string_unaccent($str)
 {
+	global $conf;
+
 	if (utf8_check($str)) {
+		if (extension_loaded('intl') && !empty($conf->global->MAIN_UNACCENT_USE_TRANSLITERATOR)) {
+			$transliterator = \Transliterator::createFromRules(':: Any-Latin; :: Latin-ASCII; :: NFD; :: [:Nonspacing Mark:] Remove; :: NFC;', \Transliterator::FORWARD);
+			return $transliterator->transliterate($str);
+		}
 		// See http://www.utf8-chartable.de/
 		$string = rawurlencode($str);
 		$replacements = array(
 		'%C3%80' => 'A', '%C3%81' => 'A', '%C3%82' => 'A', '%C3%83' => 'A', '%C3%84' => 'A', '%C3%85' => 'A',
+		'%C3%87' => 'C',
 		'%C3%88' => 'E', '%C3%89' => 'E', '%C3%8A' => 'E', '%C3%8B' => 'E',
 		'%C3%8C' => 'I', '%C3%8D' => 'I', '%C3%8E' => 'I', '%C3%8F' => 'I',
+		'%C3%91' => 'N',
 		'%C3%92' => 'O', '%C3%93' => 'O', '%C3%94' => 'O', '%C3%95' => 'O', '%C3%96' => 'O',
+		'%C5%A0' => 'S',
 		'%C3%99' => 'U', '%C3%9A' => 'U', '%C3%9B' => 'U', '%C3%9C' => 'U',
+		'%C3%9D' => 'Y', '%C5%B8' => 'y',
 		'%C3%A0' => 'a', '%C3%A1' => 'a', '%C3%A2' => 'a', '%C3%A3' => 'a', '%C3%A4' => 'a', '%C3%A5' => 'a',
 		'%C3%A7' => 'c',
 		'%C3%A8' => 'e', '%C3%A9' => 'e', '%C3%AA' => 'e', '%C3%AB' => 'e',
 		'%C3%AC' => 'i', '%C3%AD' => 'i', '%C3%AE' => 'i', '%C3%AF' => 'i',
 		'%C3%B1' => 'n',
 		'%C3%B2' => 'o', '%C3%B3' => 'o', '%C3%B4' => 'o', '%C3%B5' => 'o', '%C3%B6' => 'o',
+		'%C5%A1' => 's',
 		'%C3%B9' => 'u', '%C3%BA' => 'u', '%C3%BB' => 'u', '%C3%BC' => 'u',
-		'%C3%BF' => 'y'
+		'%C3%BD' => 'y', '%C3%BF' => 'y'
 		);
 		$string = strtr($string, $replacements);
 		return rawurldecode($string);