diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcacheSessionHandlerTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcacheSessionHandlerTest.php
index e8795244b1..0c579d7724 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcacheSessionHandlerTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcacheSessionHandlerTest.php
@@ -30,6 +30,10 @@ class MemcacheSessionHandlerTest extends \PHPUnit_Framework_TestCase
 
     protected function setUp()
     {
+        if (defined('HHVM_VERSION')) {
+            $this->markTestSkipped('PHPUnit_MockObject cannot mock the Memcache class on HHVM. See https://github.com/sebastianbergmann/phpunit-mock-objects/pull/289');
+        }
+
         parent::setUp();
         $this->memcache = $this->getMock('Memcache');
         $this->storage = new MemcacheSessionHandler(
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcachedSessionHandlerTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcachedSessionHandlerTest.php
index f51ec8ed63..75e4a20e2a 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcachedSessionHandlerTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MemcachedSessionHandlerTest.php
@@ -31,6 +31,10 @@ class MemcachedSessionHandlerTest extends \PHPUnit_Framework_TestCase
 
     protected function setUp()
     {
+        if (defined('HHVM_VERSION')) {
+            $this->markTestSkipped('PHPUnit_MockObject cannot mock the Memcached class on HHVM. See https://github.com/sebastianbergmann/phpunit-mock-objects/pull/289');
+        }
+
         parent::setUp();
 
         if (version_compare(phpversion('memcached'), '2.2.0', '>=')) {
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php
index 1af321096e..9612320976 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php
@@ -135,6 +135,10 @@ class PdoSessionHandlerTest extends \PHPUnit_Framework_TestCase
 
     public function testReadConvertsStreamToString()
     {
+        if (defined('HHVM_VERSION')) {
+            $this->markTestSkipped('PHPUnit_MockObject cannot mock the PDOStatement class on HHVM. See https://github.com/sebastianbergmann/phpunit-mock-objects/pull/289');
+        }
+
         $pdo = new MockPdo('pgsql');
         $pdo->prepareResult = $this->getMock('PDOStatement');
 
@@ -152,6 +156,10 @@ class PdoSessionHandlerTest extends \PHPUnit_Framework_TestCase
 
     public function testReadLockedConvertsStreamToString()
     {
+        if (defined('HHVM_VERSION')) {
+            $this->markTestSkipped('PHPUnit_MockObject cannot mock the PDOStatement class on HHVM. See https://github.com/sebastianbergmann/phpunit-mock-objects/pull/289');
+        }
+
         $pdo = new MockPdo('pgsql');
         $selectStmt = $this->getMock('PDOStatement');
         $insertStmt = $this->getMock('PDOStatement');