diff --git a/question/engine/lib.php b/question/engine/lib.php
index df138901268..a5e5d12f1b9 100644
--- a/question/engine/lib.php
+++ b/question/engine/lib.php
@@ -759,16 +759,16 @@ abstract class question_utils {
     public static function arrays_same_at_key_integer(
             array $array1, array $array2, $key) {
         if (array_key_exists($key, $array1)) {
-            $value1 = $array1[$key];
+            $value1 = (int) $array1[$key];
         } else {
             $value1 = 0;
         }
         if (array_key_exists($key, $array2)) {
-            $value2 = $array2[$key];
+            $value2 = (int) $array2[$key];
         } else {
             $value2 = 0;
         }
-        return ((integer) $value1) === ((integer) $value2);
+        return $value1 === $value2;
     }
 
     private static $units     = array('', 'i', 'ii', 'iii', 'iv', 'v', 'vi', 'vii', 'viii', 'ix');
diff --git a/question/type/multichoice/question.php b/question/type/multichoice/question.php
index c3ac2cab552..2888a30e890 100644
--- a/question/type/multichoice/question.php
+++ b/question/type/multichoice/question.php
@@ -338,7 +338,7 @@ class qtype_multichoice_multi_question extends qtype_multichoice_base {
     public function is_same_response(array $prevresponse, array $newresponse) {
         foreach ($this->order as $key => $notused) {
             $fieldname = $this->field($key);
-            if (!question_utils::arrays_same_at_key($prevresponse, $newresponse, $fieldname)) {
+            if (!question_utils::arrays_same_at_key_integer($prevresponse, $newresponse, $fieldname)) {
                 return false;
             }
         }
diff --git a/question/type/multichoice/tests/question_multi_test.php b/question/type/multichoice/tests/question_multi_test.php
new file mode 100644
index 00000000000..11fe16fdc57
--- /dev/null
+++ b/question/type/multichoice/tests/question_multi_test.php
@@ -0,0 +1,152 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Unit tests for the multiple choice, multi-response question definition classes.
+ *
+ * @package   qtype_multichoice
+ * @copyright 2009 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->dirroot . '/question/engine/tests/helpers.php');
+
+
+/**
+ * Unit tests for the multiple choice, multi-response question definition class.
+ *
+ * @copyright 2009 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class qtype_multichoice_multi_question_test extends advanced_testcase {
+
+    public function test_get_expected_data() {
+        $question = test_question_maker::make_a_multichoice_multi_question();
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertEquals(array('choice0' => PARAM_BOOL, 'choice1' => PARAM_BOOL,
+                'choice2' => PARAM_BOOL, 'choice3' => PARAM_BOOL), $question->get_expected_data());
+    }
+
+    public function test_is_complete_response() {
+        $question = test_question_maker::make_a_multichoice_multi_question();
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertFalse($question->is_complete_response(array()));
+        $this->assertFalse($question->is_complete_response(
+                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
+        $this->assertTrue($question->is_complete_response(array('choice1' => '1')));
+        $this->assertTrue($question->is_complete_response(
+                array('choice0' => '1', 'choice1' => '1', 'choice2' => '1', 'choice3' => '1')));
+    }
+
+    public function test_is_gradable_response() {
+        $question = test_question_maker::make_a_multichoice_multi_question();
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertFalse($question->is_gradable_response(array()));
+        $this->assertFalse($question->is_gradable_response(
+                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
+        $this->assertTrue($question->is_gradable_response(array('choice1' => '1')));
+        $this->assertTrue($question->is_gradable_response(
+                array('choice0' => '1', 'choice1' => '1', 'choice2' => '1', 'choice3' => '1')));
+    }
+
+    public function test_is_same_response() {
+        $question = test_question_maker::make_a_multichoice_multi_question();
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertTrue($question->is_same_response(
+                array(),
+                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
+
+        $this->assertTrue($question->is_same_response(
+                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0'),
+                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
+
+        $this->assertFalse($question->is_same_response(
+                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0'),
+                array('choice0' => '1', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
+
+        $this->assertTrue($question->is_same_response(
+                array('choice0' => '1', 'choice1' => '0', 'choice2' => '1', 'choice3' => '0'),
+                array('choice0' => '1', 'choice1' => '0', 'choice2' => '1', 'choice3' => '0')));
+    }
+
+    public function test_grading() {
+        $question = test_question_maker::make_a_multichoice_multi_question();
+        $question->shuffleanswers = false;
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertEquals(array(1, question_state::$gradedright),
+                $question->grade_response(array('choice0' => '1', 'choice2' => '1')));
+        $this->assertEquals(array(0.5, question_state::$gradedpartial),
+                $question->grade_response(array('choice0' => '1')));
+        $this->assertEquals(array(0, question_state::$gradedwrong),
+                $question->grade_response(
+                        array('choice0' => '1', 'choice1' => '1', 'choice2' => '1')));
+        $this->assertEquals(array(0, question_state::$gradedwrong),
+                $question->grade_response(array('choice1' => '1')));
+    }
+
+    public function test_get_correct_response() {
+        $question = test_question_maker::make_a_multichoice_multi_question();
+        $question->shuffleanswers = false;
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertEquals(array('choice0' => '1', 'choice2' => '1'),
+                $question->get_correct_response());
+    }
+
+    public function test_get_question_summary() {
+        $mc = test_question_maker::make_a_multichoice_single_question();
+        $mc->start_attempt(new question_attempt_step(), 1);
+
+        $qsummary = $mc->get_question_summary();
+
+        $this->assertRegExp('/' . preg_quote($mc->questiontext, '/') . '/', $qsummary);
+        foreach ($mc->answers as $answer) {
+            $this->assertRegExp('/' . preg_quote($answer->answer, '/') . '/', $qsummary);
+        }
+    }
+
+    public function test_summarise_response() {
+        $mc = test_question_maker::make_a_multichoice_multi_question();
+        $mc->shuffleanswers = false;
+        $mc->start_attempt(new question_attempt_step(), 1);
+
+        $summary = $mc->summarise_response(array('choice1' => 1, 'choice2' => 1),
+                test_question_maker::get_a_qa($mc));
+
+        $this->assertEquals('B; C', $summary);
+    }
+
+    public function test_classify_response() {
+        $mc = test_question_maker::make_a_multichoice_multi_question();
+        $mc->shuffleanswers = false;
+        $mc->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertEquals(array(
+                    13 => new question_classified_response(13, 'A', 0.5),
+                    14 => new question_classified_response(14, 'B', -1.0),
+                ), $mc->classify_response(array('choice0' => 1, 'choice1' => 1)));
+
+        $this->assertEquals(array(), $mc->classify_response(array()));
+    }
+}
diff --git a/question/type/multichoice/tests/question_test.php b/question/type/multichoice/tests/question_single_test.php
similarity index 56%
rename from question/type/multichoice/tests/question_test.php
rename to question/type/multichoice/tests/question_single_test.php
index 9e44f816826..335b2460c45 100644
--- a/question/type/multichoice/tests/question_test.php
+++ b/question/type/multichoice/tests/question_single_test.php
@@ -15,15 +15,13 @@
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
 
 /**
- * Unit tests for the multiple choice question definition classes.
+ * Unit tests for the multiple choice, single response question definition classes.
  *
- * @package    qtype
- * @subpackage multichoice
- * @copyright  2009 The Open University
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   qtype_multichoice
+ * @copyright 2009 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-
 defined('MOODLE_INTERNAL') || die();
 
 global $CFG;
@@ -31,10 +29,10 @@ require_once($CFG->dirroot . '/question/engine/tests/helpers.php');
 
 
 /**
- * Unit tests for the multiple choice, multiple response question definition class.
+ * Unit tests for the multiple choice, single response question definition class.
  *
- * @copyright  2009 The Open University
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @copyright 2009 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class qtype_multichoice_single_question_test extends advanced_testcase {
 
@@ -59,6 +57,31 @@ class qtype_multichoice_single_question_test extends advanced_testcase {
         $this->assertTrue($question->is_gradable_response(array('answer' => '2')));
     }
 
+    public function test_is_same_response() {
+        $question = test_question_maker::make_a_multichoice_single_question();
+        $question->start_attempt(new question_attempt_step(), 1);
+
+        $this->assertTrue($question->is_same_response(
+                array(),
+                array()));
+
+        $this->assertFalse($question->is_same_response(
+                array(),
+                array('answer' => '0')));
+
+        $this->assertTrue($question->is_same_response(
+                array('answer' => '0'),
+                array('answer' => '0')));
+
+        $this->assertFalse($question->is_same_response(
+                array('answer' => '0'),
+                array('answer' => '1')));
+
+        $this->assertTrue($question->is_same_response(
+                array('answer' => '2'),
+                array('answer' => '2')));
+    }
+
     public function test_grading() {
         $question = test_question_maker::make_a_multichoice_single_question();
         $question->shuffleanswers = false;
@@ -151,106 +174,3 @@ class qtype_multichoice_single_question_test extends advanced_testcase {
         $this->assertEquals('Frog<br />†', $mc->make_html_inline('<p>Frog</p><p>†</p>'));
     }
 }
-
-
-/**
- * Unit tests for the multiple choice, single response question definition class.
- *
- * @copyright  2009 The Open University
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
-class qtype_multichoice_multi_question_test extends advanced_testcase {
-
-    public function test_get_expected_data() {
-        $question = test_question_maker::make_a_multichoice_multi_question();
-        $question->start_attempt(new question_attempt_step(), 1);
-
-        $this->assertEquals(array('choice0' => PARAM_BOOL, 'choice1' => PARAM_BOOL,
-                'choice2' => PARAM_BOOL, 'choice3' => PARAM_BOOL), $question->get_expected_data());
-    }
-
-    public function test_is_complete_response() {
-        $question = test_question_maker::make_a_multichoice_multi_question();
-        $question->start_attempt(new question_attempt_step(), 1);
-
-        $this->assertFalse($question->is_complete_response(array()));
-        $this->assertFalse($question->is_complete_response(
-                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
-        $this->assertTrue($question->is_complete_response(array('choice1' => '1')));
-        $this->assertTrue($question->is_complete_response(
-                array('choice0' => '1', 'choice1' => '1', 'choice2' => '1', 'choice3' => '1')));
-    }
-
-    public function test_is_gradable_response() {
-        $question = test_question_maker::make_a_multichoice_multi_question();
-        $question->start_attempt(new question_attempt_step(), 1);
-
-        $this->assertFalse($question->is_gradable_response(array()));
-        $this->assertFalse($question->is_gradable_response(
-                array('choice0' => '0', 'choice1' => '0', 'choice2' => '0', 'choice3' => '0')));
-        $this->assertTrue($question->is_gradable_response(array('choice1' => '1')));
-        $this->assertTrue($question->is_gradable_response(
-                array('choice0' => '1', 'choice1' => '1', 'choice2' => '1', 'choice3' => '1')));
-    }
-
-    public function test_grading() {
-        $question = test_question_maker::make_a_multichoice_multi_question();
-        $question->shuffleanswers = false;
-        $question->start_attempt(new question_attempt_step(), 1);
-
-        $this->assertEquals(array(1, question_state::$gradedright),
-                $question->grade_response(array('choice0' => '1', 'choice2' => '1')));
-        $this->assertEquals(array(0.5, question_state::$gradedpartial),
-                $question->grade_response(array('choice0' => '1')));
-        $this->assertEquals(array(0, question_state::$gradedwrong),
-                $question->grade_response(
-                        array('choice0' => '1', 'choice1' => '1', 'choice2' => '1')));
-        $this->assertEquals(array(0, question_state::$gradedwrong),
-                $question->grade_response(array('choice1' => '1')));
-    }
-
-    public function test_get_correct_response() {
-        $question = test_question_maker::make_a_multichoice_multi_question();
-        $question->shuffleanswers = false;
-        $question->start_attempt(new question_attempt_step(), 1);
-
-        $this->assertEquals(array('choice0' => '1', 'choice2' => '1'),
-                $question->get_correct_response());
-    }
-
-    public function test_get_question_summary() {
-        $mc = test_question_maker::make_a_multichoice_single_question();
-        $mc->start_attempt(new question_attempt_step(), 1);
-
-        $qsummary = $mc->get_question_summary();
-
-        $this->assertRegExp('/' . preg_quote($mc->questiontext, '/') . '/', $qsummary);
-        foreach ($mc->answers as $answer) {
-            $this->assertRegExp('/' . preg_quote($answer->answer, '/') . '/', $qsummary);
-        }
-    }
-
-    public function test_summarise_response() {
-        $mc = test_question_maker::make_a_multichoice_multi_question();
-        $mc->shuffleanswers = false;
-        $mc->start_attempt(new question_attempt_step(), 1);
-
-        $summary = $mc->summarise_response(array('choice1' => 1, 'choice2' => 1),
-                test_question_maker::get_a_qa($mc));
-
-        $this->assertEquals('B; C', $summary);
-    }
-
-    public function test_classify_response() {
-        $mc = test_question_maker::make_a_multichoice_multi_question();
-        $mc->shuffleanswers = false;
-        $mc->start_attempt(new question_attempt_step(), 1);
-
-        $this->assertEquals(array(
-                    13 => new question_classified_response(13, 'A', 0.5),
-                    14 => new question_classified_response(14, 'B', -1.0),
-                ), $mc->classify_response(array('choice0' => 1, 'choice1' => 1)));
-
-        $this->assertEquals(array(), $mc->classify_response(array()));
-    }
-}