diff --git a/UPGRADE-3.0.md b/UPGRADE-3.0.md
index 855056b682..96f6f8285c 100644
--- a/UPGRADE-3.0.md
+++ b/UPGRADE-3.0.md
@@ -707,10 +707,9 @@ UPGRADE FROM 2.x to 3.0
    ```php
    class MyVoter extends AbstractVoter
    {
-       protected function supports($attribute, $class)
+       protected function supports($attribute, $object)
        {
-           return $this->isClassInstanceOf($class, 'AppBundle\Entity\Post')
-               && in_array($attribute, array('CREATE', 'EDIT'));
+           return $object instanceof Post && in_array($attribute, array('CREATE', 'EDIT'));
        }
 
        // ...
diff --git a/src/Symfony/Component/Security/Core/Authorization/Voter/AbstractVoter.php b/src/Symfony/Component/Security/Core/Authorization/Voter/AbstractVoter.php
index 799c6f7c4d..7b04222eae 100644
--- a/src/Symfony/Component/Security/Core/Authorization/Voter/AbstractVoter.php
+++ b/src/Symfony/Component/Security/Core/Authorization/Voter/AbstractVoter.php
@@ -68,10 +68,9 @@ abstract class AbstractVoter implements VoterInterface
 
         // abstain vote by default in case none of the attributes are supported
         $vote = self::ACCESS_ABSTAIN;
-        $class = get_class($object);
 
         foreach ($attributes as $attribute) {
-            if (!$this->supports($attribute, $class)) {
+            if (!$this->supports($attribute, $object)) {
                 continue;
             }
 
@@ -88,25 +87,22 @@ abstract class AbstractVoter implements VoterInterface
     }
 
     /**
-     * Determines if the attribute and class are supported by this voter.
-     *
-     * To determine if the passed class is instance of the supported class, the
-     * isClassInstanceOf() method can be used.
+     * Determines if the attribute and object are supported by this voter.
      *
      * This method will become abstract in 3.0.
      *
      * @param string $attribute An attribute
-     * @param string $class     The fully qualified class name of the passed object
+     * @param string $object    The object to secure
      *
-     * @return bool True if the attribute and class is supported, false otherwise
+     * @return bool True if the attribute and object is supported, false otherwise
      */
-    protected function supports($attribute, $class)
+    protected function supports($attribute, $object)
     {
         @trigger_error('The getSupportedClasses and getSupportedAttributes methods are deprecated since version 2.8 and will be removed in version 3.0. Overwrite supports instead.', E_USER_DEPRECATED);
 
         $classIsSupported = false;
         foreach ($this->getSupportedClasses() as $supportedClass) {
-            if ($this->isClassInstanceOf($class, $supportedClass)) {
+            if ($object instanceof $supportedClass) {
                 $classIsSupported = true;
                 break;
             }
@@ -123,20 +119,6 @@ abstract class AbstractVoter implements VoterInterface
         return true;
     }
 
-    /**
-     * A helper method to test if the actual class is instanceof or equal
-     * to the expected class.
-     *
-     * @param string $actualClass   The actual class name
-     * @param string $expectedClass The expected class name
-     *
-     * @return bool
-     */
-    protected function isClassInstanceOf($actualClass, $expectedClass)
-    {
-        return $expectedClass === $actualClass || is_subclass_of($actualClass, $expectedClass);
-    }
-
     /**
      * Return an array of supported classes. This will be called by supportsClass.
      *
diff --git a/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/AbstractVoterTest.php b/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/AbstractVoterTest.php
index 7062d3983b..5ea77320cf 100644
--- a/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/AbstractVoterTest.php
+++ b/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/AbstractVoterTest.php
@@ -84,10 +84,9 @@ class AbstractVoterTest_Voter extends AbstractVoter
         return 'EDIT' === $attribute;
     }
 
-    protected function supports($attribute, $class)
+    protected function supports($attribute, $object)
     {
-        return $this->isClassInstanceOf($class, 'stdClass')
-            && in_array($attribute, array('EDIT', 'CREATE'));
+        return $object instanceof \stdClass && in_array($attribute, array('EDIT', 'CREATE'));
     }
 }