diff --git a/grade/grading/simpletest/testlib.php b/grade/grading/simpletest/testlib.php
index ea3c4130f9e..3e489b8c493 100644
--- a/grade/grading/simpletest/testlib.php
+++ b/grade/grading/simpletest/testlib.php
@@ -131,11 +131,13 @@ class grading_manager_test extends UnitTestCase {
 
     public function test_tokenize() {
 
+        $UTFfailuremessage = 'A test using UTF-8 characters has failed. Consider updating PHP and PHP\'s PCRE or INTL extensions (MDL-30494)';
+
         $needle = "    šašek, \n\n   \r    a král;  \t";
         $tokens = testable_grading_manager::tokenize($needle);
-        $this->assertEqual(2, count($tokens));
-        $this->assertTrue(in_array('šašek', $tokens));
-        $this->assertTrue(in_array('král', $tokens));
+        $this->assertEqual(2, count($tokens), $UTFfailuremessage);
+        $this->assertTrue(in_array('šašek', $tokens), $UTFfailuremessage);
+        $this->assertTrue(in_array('král', $tokens), $UTFfailuremessage);
 
         $needle = ' "   šašek a král "    ';
         $tokens = testable_grading_manager::tokenize($needle);