diff --git a/upload/system/helper/utf8.php b/upload/system/helper/utf8.php
index <HASH>..<HASH> 100644
--- a/upload/system/helper/utf8.php
+++ b/upload/system/helper/utf8.php
@@ -15,7 +15,7 @@ if (extension_loaded('mbstring')) {
 	}

 	

 	function utf8_substr($string, $offset, $length = null) {

-		if ($length == null) {

+		if ($length === null) {

 			return mb_substr($string, $offset, utf8_strlen($string));

 		} else {

 			return mb_substr($string, $offset, $length);

@@ -43,7 +43,7 @@ if (extension_loaded('mbstring')) {
 	}

 	

 	function utf8_substr($string, $offset, $length = null) {

-		if ($length == null) {

+		if ($length === null) {

 			return iconv_substr($string, $offset, utf8_strlen($string), 'UTF-8');

 		} else {

 			return iconv_substr($string, $offset, $length, 'UTF-8');
utf8_substr fix

Should fix upgrade issues caused by PHP considering int 0 equal to null