diff --git a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
index a10d8c866..f556257f9 100644
--- a/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
+++ b/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php
@@ -1628,6 +1628,7 @@ class ClassMetadataInfo implements ClassMetadata
             if (strpos($className, '\\') === false && strlen($this->namespace)) {
                 $className = $this->namespace . '\\' . $className;
             }
+            $className = ltrim($className, '\\');
             $this->discriminatorMap[$value] = $className;
             if ($this->name == $className) {
                 $this->discriminatorValue = $value;