diff --git a/ext/soap/tests/bugs/bug39815.phpt b/ext/soap/tests/bugs/bug39815.phpt
index 3400e9d0c62..e23c6b96d19 100755
--- a/ext/soap/tests/bugs/bug39815.phpt
+++ b/ext/soap/tests/bugs/bug39815.phpt
@@ -4,7 +4,8 @@ Bug #39815 (to_zval_double() in ext/soap/php_encoding.c is not locale-independen
 <?php 
 require_once('skipif.inc'); 
 if (!function_exists('setlocale')) die('skip setlocale() not available'); 
-if (!@setlocale(LC_ALL, 'sv_SE')) die('skip sv_SE locale not available');
+if (!@setlocale(LC_ALL, 'sv_SE', 'sv_SE.ISO8859-1')) die('skip sv_SE locale not available');
+if (!@setlocale(LC_ALL, 'en_US', 'en_US.ISO8859-1')) die('skip en_US locale not available');
 ?>
 --FILE--
 <?php
@@ -31,10 +32,10 @@ class LocalSoapClient extends SoapClient {
 $x = new LocalSoapClient(NULL,array('location'=>'test://', 
                                    'uri'=>'http://testuri.org',
                                    "trace"=>1)); 
-@setlocale(LC_ALL,"sv_SE");
+setlocale(LC_ALL,"sv_SE","sv_SE.ISO8859-1");
 var_dump($x->test());
 echo $x->__getLastResponse();
-@setlocale(LC_ALL,"en_US");
+setlocale(LC_ALL,"en_US","en_US.ISO8859-1");
 var_dump($x->test());
 echo $x->__getLastResponse();
 --EXPECT--