diff --git a/mod/lti/servicelib.php b/mod/lti/servicelib.php
index 18d58012fdf..741321156d3 100644
--- a/mod/lti/servicelib.php
+++ b/mod/lti/servicelib.php
@@ -37,7 +37,7 @@ define('LTI_SOURCE', 'mod/lti');
 
 function lti_get_response_xml($codemajor, $description, $messageref, $messagetype) {
     $xml = new SimpleXMLElement('<?xml version="1.0" encoding="UTF-8"?><imsx_POXEnvelopeResponse />');
-    $xml->addAttribute('xmlns', 'http://www.imsglobal.org/lis/oms1p0/pox');
+    $xml->addAttribute('xmlns', 'http://www.imsglobal.org/services/ltiv1p1/xsd/imsoms_v1p0');
 
     $headerinfo = $xml->addChild('imsx_POXHeader')->addChild('imsx_POXResponseHeaderInfo');
 
diff --git a/mod/lti/tests/locallib_test.php b/mod/lti/tests/locallib_test.php
index 7ffb74f686e..2c3f3925b04 100644
--- a/mod/lti/tests/locallib_test.php
+++ b/mod/lti/tests/locallib_test.php
@@ -104,7 +104,7 @@ class mod_lti_locallib_testcase extends basic_testcase {
      */
     public function disabled_test_parse_grade_replace_message() {
         $message = '
-            <imsx_POXEnvelopeRequest xmlns = "http://www.imsglobal.org/lis/oms1p0/pox">
+            <imsx_POXEnvelopeRequest xmlns = "http://www.imsglobal.org/services/ltiv1p1/xsd/imsoms_v1p0">
               <imsx_POXHeader>
                 <imsx_POXRequestHeaderInfo>
                   <imsx_version>V1.0</imsx_version>