diff --git a/lib/Doctrine/ORM/Mapping/Driver/DriverChain.php b/lib/Doctrine/ORM/Mapping/Driver/DriverChain.php
index d97a61e5b..77c258a18 100644
--- a/lib/Doctrine/ORM/Mapping/Driver/DriverChain.php
+++ b/lib/Doctrine/ORM/Mapping/Driver/DriverChain.php
@@ -88,10 +88,15 @@ class DriverChain implements Driver
     public function getAllClassNames()
     {
         $classNames = array();
-        foreach ($this->_drivers AS $driver) {
-            $classNames = array_merge($classNames, $driver->getAllClassNames());
+        foreach ($this->_drivers AS $namespace => $driver) {
+            $driverClasses = $driver->getAllClassNames();
+            foreach ($driverClasses AS $className) {
+                if (strpos($className, $namespace) === 0) {
+                    $classNames[] = $className;
+                }
+            }
         }
-        return $classNames;
+        return array_unique($classNames);
     }
 
     /**
diff --git a/tests/Doctrine/Tests/ORM/Mapping/DriverChainTest.php b/tests/Doctrine/Tests/ORM/Mapping/DriverChainTest.php
index 333b8638b..d218aaf8f 100644
--- a/tests/Doctrine/Tests/ORM/Mapping/DriverChainTest.php
+++ b/tests/Doctrine/Tests/ORM/Mapping/DriverChainTest.php
@@ -60,17 +60,21 @@ class DriverChainTest extends \Doctrine\Tests\OrmTestCase
         $driver1 = $this->getMock('Doctrine\ORM\Mapping\Driver\Driver');
         $driver1->expects($this->once())
                 ->method('getAllClassNames')
-                ->will($this->returnValue(array('Foo')));
+                ->will($this->returnValue(array('Doctrine\Tests\Models\Company\Foo')));
 
         $driver2 = $this->getMock('Doctrine\ORM\Mapping\Driver\Driver');
         $driver2->expects($this->once())
                 ->method('getAllClassNames')
-                ->will($this->returnValue(array('Bar', 'Baz')));
+                ->will($this->returnValue(array('Doctrine\Tests\ORM\Mapping\Bar', 'Doctrine\Tests\ORM\Mapping\Baz', 'FooBarBaz')));
 
         $chain->addDriver($driver1, 'Doctrine\Tests\Models\Company');
         $chain->addDriver($driver2, 'Doctrine\Tests\ORM\Mapping');
 
-        $this->assertEquals(array('Foo', 'Bar', 'Baz'), $chain->getAllClassNames());
+        $this->assertEquals(array(
+            'Doctrine\Tests\Models\Company\Foo',
+            'Doctrine\Tests\ORM\Mapping\Bar',
+            'Doctrine\Tests\ORM\Mapping\Baz'
+        ), $chain->getAllClassNames());
     }
 
     /**