diff --git a/content/smil/test/Makefile.in b/content/smil/test/Makefile.in
index 8ff8c40e0e04..6416ab66c7e1 100644
--- a/content/smil/test/Makefile.in
+++ b/content/smil/test/Makefile.in
@@ -50,6 +50,7 @@ _TEST_FILES = \
 	  db_smilCSSPaced.js \
 	  db_smilCSSPropertyList.js \
 	  smilTestUtils.js \
+	  smilXHR_helper.svg \
 	  test_smilCSSFontStretchRelative.xhtml \
 	  test_smilCSSFromBy.xhtml \
 	  test_smilCSSFromTo.xhtml \
@@ -65,6 +66,7 @@ _TEST_FILES = \
 	  test_smilTextZoom.xhtml \
 	  test_smilTiming.xhtml \
 	  test_smilTimingZeroIntervals.xhtml \
+	  test_smilXHR.xhtml \
 		$(NULL)
 
 libs:: $(_TEST_FILES)
diff --git a/content/smil/test/smilXHR_helper.svg b/content/smil/test/smilXHR_helper.svg
new file mode 100644
index 000000000000..cb0b51c36052
--- /dev/null
+++ b/content/smil/test/smilXHR_helper.svg
@@ -0,0 +1,8 @@
+<svg id="svg" xmlns="http://www.w3.org/2000/svg" width="120px" height="120px">
+  <circle id="circ" cx="20" cy="20" r="15" fill="blue">
+    <animate id="animXML" attributeName="cx" attributeType="XML"
+             from="500" to="600" begin="0s" dur="4s"/>
+    <animate id="animCSS" attributeName="opacity" attributeType="CSS"
+             from="0.2" to="0.3" begin="0s" dur="4s"/>
+  </circle>
+</svg>
diff --git a/content/smil/test/test_smilXHR.xhtml b/content/smil/test/test_smilXHR.xhtml
new file mode 100644
index 000000000000..85c86114d94a
--- /dev/null
+++ b/content/smil/test/test_smilXHR.xhtml
@@ -0,0 +1,89 @@
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head>
+  <title>Test for SMIL Behavior in Data Documents</title>
+  <script type="text/javascript" src="/MochiKit/packed.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="smilTestUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=529387">Mozilla Bug 529387</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+</div>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+<![CDATA[
+/** Test for SMIL Behavior in Data Documents, with XMLHttpRequest **/
+
+SimpleTest.waitForExplicitFinish();
+
+function tryPausing(svg) {
+  // Check that pausing has no effect
+  ok(!svg.animationsPaused(),
+     "shouldn't be paused (because we shouldn't have even started");
+  svg.pauseAnimations();
+  ok(!svg.animationsPaused(), "attempts to pause should have no effect");
+  svg.unpauseAnimations();
+  ok(!svg.animationsPaused(), "still shouldn't be paused, after pause/unpause");
+}
+
+function trySeeking(svg) {
+  // Check that seeking is ineffective
+  is(svg.getCurrentTime(), 0, "should start out at time=0");
+  svg.setCurrentTime(1);
+  is(svg.getCurrentTime(), 0, "shouldn't be able to seek away from time=0");
+}
+
+function tryBeginEnd(anim) {
+  // Check that beginning / ending a particular animation element will trigger
+  // exceptions.
+  var didThrow = false;
+  ok(anim, "need a non-null animate element");
+  try {
+     anim.beginElement();
+  } catch (e) {
+    didThrow = true;
+  }
+  ok(didThrow, "beginElement should fail");
+
+  didThrow = false;
+  try {
+    anim.endElement();
+  } catch (e) {
+    didThrow = true;
+  }
+  ok(didThrow, "endElement should fail");
+}
+
+function main() {
+  var xhr = new XMLHttpRequest();
+  xhr.open("GET", "smilXHR_helper.svg", false);
+  xhr.send();
+  var xdoc = xhr.responseXML;
+
+  var svg  = xdoc.getElementById("svg");
+  var circ = xdoc.getElementById("circ");
+  var animXML = xdoc.getElementById("animXML");
+  var animCSS = xdoc.getElementById("animCSS");
+
+  tryPausing(svg);
+  trySeeking(svg);
+  tryBeginEnd(animXML);
+  tryBeginEnd(animCSS);
+
+  // Check that the actual values of our animated attr/prop aren't affected
+  is(circ.cx.animVal.value, circ.cx.baseVal.value,
+     "animation of attribute shouldn't be taking effect");
+  is(SMILUtil.getComputedStyleSimple(circ, "opacity"), "1",
+     "animation of CSS property shouldn't be taking effect");
+ 
+  SimpleTest.finish();
+}
+
+window.addEventListener("load", main, false);
+]]>
+</script>
+</pre>
+</body>
+</html>
