diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 68c61886efd..1450e2f100f 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -373,38 +373,43 @@ function dol_string_unaccent($str)
 {
 	if (utf8_check($str))
 	{
+		// See http://www.utf8-chartable.de/
 		$string = rawurlencode($str);
 		$replacements = array(
-		'%C3%80' => 'A','%C3%81' => 'A',
-		'%C3%88' => 'E','%C3%89' => 'E',
-		'%C3%8C' => 'I','%C3%8D' => 'I',
-		'%C3%92' => 'O','%C3%93' => 'O',
-		'%C3%99' => 'U','%C3%9A' => 'U',
-		'%C3%A0' => 'a','%C3%A1' => 'a','%C3%A2' => 'a',
+		'%C3%80' => 'A','%C3%81' => 'A','%C3%82' => 'A','%C3%83' => 'A','%C3%84' => 'A','%C3%85' => 'A',
+		'%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%92' => 'O','%C3%93' => 'O','%C3%94' => 'O','%C3%95' => 'O','%C3%96' => 'O',
+		'%C3%99' => 'U','%C3%9A' => 'U','%C3%9B' => 'U','%C3%9C' => 'U',
+		'%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%B2' => 'o','%C3%B3' => 'o',
-		'%C3%B9' => 'u','%C3%BA' => 'u'
+		'%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',
+		'%C3%B9' => 'u','%C3%BA' => 'u','%C3%BB' => 'u','%C3%BC' => 'u',
+		'%C3%BF' => 'y'
 		);
 		$string=strtr($string, $replacements);
 		return rawurldecode($string);
 	}
 	else
 	{
+		// See http://www.ascii-code.com/
 		$string = strtr(
 			$str,
-			"\xC0\xC1\xC2\xC3\xC5\xC7
+			"\xC0\xC1\xC2\xC3\xC4\xC5\xC7
 			\xC8\xC9\xCA\xCB\xCC\xCD\xCE\xCF\xD0\xD1
 			\xD2\xD3\xD4\xD5\xD8\xD9\xDA\xDB\xDD
-			\xE0\xE1\xE2\xE3\xE5\xE7\xE8\xE9\xEA\xEB
+			\xE0\xE1\xE2\xE3\xE4\xE5\xE7\xE8\xE9\xEA\xEB
 			\xEC\xED\xEE\xEF\xF0\xF1\xF2\xF3\xF4\xF5\xF8
-			\xF9\xFA\xFB\xFD\xFF",
-			"AAAAAC
+			\xF9\xFA\xFB\xFC\xFD\xFF",
+			"AAAAAAC
 			EEEEIIIIDN
 			OOOOOUUUY
-			aaaaaceeee
+			aaaaaaceeee
 			iiiidnooooo
-			uuuyy"
+			uuuuyy"
 		);
 		$string = strtr($string, array("\xC4"=>"Ae", "\xC6"=>"AE", "\xD6"=>"Oe", "\xDC"=>"Ue", "\xDE"=>"TH", "\xDF"=>"ss", "\xE4"=>"ae", "\xE6"=>"ae", "\xF6"=>"oe", "\xFC"=>"ue", "\xFE"=>"th"));
 		return $string;
diff --git a/test/phpunit/FunctionsLibTest.php b/test/phpunit/FunctionsLibTest.php
index 2178ad6fb5a..dbb3f6d8b8d 100755
--- a/test/phpunit/FunctionsLibTest.php
+++ b/test/phpunit/FunctionsLibTest.php
@@ -364,7 +364,22 @@ class FunctionsLibTest extends PHPUnit_Framework_TestCase
 
 
     /**
-     * testDolTextIsHtml
+     * testDolUnaccent
+     *
+     * @return boolean
+     */
+    public function testDolUnaccent()
+    {
+    	// Text not already HTML
+
+    	$input="A string\nwith a à ä é è ë ï ü ö ÿ, &, < and >.";
+        $after=dol_string_unaccent($input);
+        $this->assertEquals("A string\nwith a a a e e e i u o y, &, < and >.",$after);
+    }
+
+
+    /**
+     * testDolUtf8Check
      *
      * @return void
      */