diff --git a/aop/AopCertClient.php b/aop/AopCertClient.php
index e44371db60..a33695a0df 100644
--- a/aop/AopCertClient.php
+++ b/aop/AopCertClient.php
@@ -386,7 +386,7 @@ public function rsaDecrypt($data, $rsaPrivateKeyPem, $charset) {
         return $strnull;
     }
 
-    function splitCN($cont, $n = 0, $subnum, $charset) {
+    function splitCN($cont, $n, $subnum, $charset) {
         //$len = strlen($cont) / 3;
         $arrr = array();
         for ($i = $n; $i < strlen($cont); $i += $subnum) {
@@ -399,7 +399,7 @@ function splitCN($cont, $n = 0, $subnum, $charset) {
         return $arrr;
     }
 
-    function subCNchar($str, $start = 0, $length, $charset = "gbk") {
+    function subCNchar($str, $start, $length, $charset = "gbk") {
         if (strlen($str) <= $length) {
             return $str;
         }
@@ -1300,4 +1300,4 @@ function echoDebug($content) {
             echo "<br/>" . $content;
         }
     }
-}
\ No newline at end of file
+}