diff --git a/lib/Doctrine/ORM/Mapping/ClassMetadata.php b/lib/Doctrine/ORM/Mapping/ClassMetadata.php
index 808e58552..4e31f5578 100644
--- a/lib/Doctrine/ORM/Mapping/ClassMetadata.php
+++ b/lib/Doctrine/ORM/Mapping/ClassMetadata.php
@@ -20,6 +20,7 @@
 namespace Doctrine\ORM\Mapping;
 
 use ReflectionClass, ReflectionProperty;
+use Doctrine\Common\Persistence\Mapping\ClassMetadata AS IClassMetadata;
 
 /**
  * A <tt>ClassMetadata</tt> instance holds all the object-relational mapping metadata
@@ -39,7 +40,7 @@ use ReflectionClass, ReflectionProperty;
  * @author Jonathan H. Wage <jonwage@gmail.com>
  * @since 2.0
  */
-class ClassMetadata extends ClassMetadataInfo
+class ClassMetadata extends ClassMetadataInfo implements IClassMetadata
 {
     /**
      * The ReflectionProperty instances of the mapped class.
diff --git a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
index d845e6f59..6fbf8b3c6 100644
--- a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
+++ b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
@@ -19,7 +19,6 @@
 
 namespace Doctrine\ORM\Mapping;
 
-use Doctrine\Common\Persistence\Mapping\ClassMetadata;
 use Doctrine\DBAL\Types\Type;
 use ReflectionClass;
 
@@ -41,7 +40,7 @@ use ReflectionClass;
  * @author Jonathan H. Wage <jonwage@gmail.com>
  * @since 2.0
  */
-class ClassMetadataInfo implements ClassMetadata
+class ClassMetadataInfo
 {
     /* The inheritance mapping types */
     /**
diff --git a/lib/vendor/doctrine-common b/lib/vendor/doctrine-common
index 9c880cf9a..ef7382756 160000
--- a/lib/vendor/doctrine-common
+++ b/lib/vendor/doctrine-common
@@ -1 +1 @@
-Subproject commit 9c880cf9ae2c14102568520b5ee885b03bda93e4
+Subproject commit ef7382756672d99c92b746aea56f10295edfc96b