diff --git a/modules/@angular/core/testing/testing.ts b/modules/@angular/core/testing/testing.ts
index b062b25f62..b5a297d243 100644
--- a/modules/@angular/core/testing/testing.ts
+++ b/modules/@angular/core/testing/testing.ts
@@ -2,7 +2,7 @@
  * Public Test Library for unit testing Angular2 Applications. Uses the
  * Jasmine framework.
  */
-import {isPromise} from '../src/facade/lang';
+import {isPromise, isString} from '../src/facade/lang';
 
 import {TestInjector, async, getTestInjector, inject, injectAsync} from './test_injector';
 
@@ -108,7 +108,12 @@ function _wrapTestFn(fn: Function) {
       let retVal = fn();
       if (isPromise(retVal)) {
         // Asynchronous test function - wait for completion.
-        (<Promise<any>>retVal).then(done, done.fail);
+        (<Promise<any>>retVal).then(done, (err) => {
+          if (isString(err)) {
+            return done.fail(new Error(err));
+          }
+          return done.fail(err);
+        });
       } else {
         // Synchronous test function - complete immediately.
         done();
diff --git a/modules/@angular/platform-browser-dynamic/test/testing_public_browser_spec.ts b/modules/@angular/platform-browser-dynamic/test/testing_public_browser_spec.ts
index 2f11a57ab8..5b74552194 100644
--- a/modules/@angular/platform-browser-dynamic/test/testing_public_browser_spec.ts
+++ b/modules/@angular/platform-browser-dynamic/test/testing_public_browser_spec.ts
@@ -142,7 +142,8 @@ export function main() {
         itPromise.then(
             () => { done.fail('Expected test to fail, but it did not'); },
             (err) => {
-              expect(err).toEqual('Uncaught (in promise): Failed to load non-existant.html');
+              expect(err.message)
+                  .toEqual('Uncaught (in promise): Failed to load non-existant.html');
               done();
             });
         restoreJasmineIt();
diff --git a/modules/@angular/platform-browser/test/testing_public_spec.ts b/modules/@angular/platform-browser/test/testing_public_spec.ts
index 86f909cc74..ee2b45ead4 100644
--- a/modules/@angular/platform-browser/test/testing_public_spec.ts
+++ b/modules/@angular/platform-browser/test/testing_public_spec.ts
@@ -231,14 +231,15 @@ export function main() {
 
     it('should fail when an asynchronous error is thrown', (done: any /** TODO #9100 */) => {
       var itPromise = patchJasmineIt();
+      var barError = new Error('bar');
 
       it('throws an async error',
-         async(inject([], () => { setTimeout(() => { throw new Error('bar'); }, 0); })));
+         async(inject([], () => { setTimeout(() => { throw barError; }, 0); })));
 
       itPromise.then(
           () => { done.fail('Expected test to fail, but it did not'); },
           (err) => {
-            expect(err).toEqual('bar');
+            expect(err).toEqual(barError);
             done();
           });
       restoreJasmineIt();
@@ -258,7 +259,7 @@ export function main() {
       itPromise.then(
           () => { done.fail('Expected test to fail, but it did not'); },
           (err) => {
-            expect(err).toEqual('Uncaught (in promise): baz');
+            expect(err.message).toEqual('Uncaught (in promise): baz');
             done();
           });
       restoreJasmineIt();