diff --git a/zephyr/tests/frontend/tests.js b/zephyr/tests/frontend/tests.js
index 3d5f14d812..e9b00163d2 100644
--- a/zephyr/tests/frontend/tests.js
+++ b/zephyr/tests/frontend/tests.js
@@ -120,6 +120,21 @@ function un_narrow() {
 
 // Start of test script.
 casper.start('http://localhost:9981/', function () {
+    // Fail if we get a JavaScript error in the page's context.
+    // Based on the example at http://phantomjs.org/release-1.5.html
+    //
+    // casper.on('error') doesn't work (it never gets called) so we
+    // set this at the PhantomJS level.  We do it inside 'start' so
+    // that we know we have a page object.
+    casper.page.onError = function (msg, trace) {
+        casper.test.error(msg);
+        casper.echo('Traceback:');
+        trace.forEach(function (item) {
+            casper.echo('  ' + item.file + ':' + item.line);
+        });
+        casper.exit(1);
+    };
+
     casper.test.assertHttpStatus(302);
     casper.test.assertUrlMatch(/^http:\/\/[^\/]+\/accounts\/home/, 'Redirected to /accounts/home');
     casper.click('a[href^="/accounts/login"]');