diff --git a/lib/Doctrine/ORM/Tools/Export/Driver/XmlExporter.php b/lib/Doctrine/ORM/Tools/Export/Driver/XmlExporter.php
index 1a8fde184..33253b668 100644
--- a/lib/Doctrine/ORM/Tools/Export/Driver/XmlExporter.php
+++ b/lib/Doctrine/ORM/Tools/Export/Driver/XmlExporter.php
@@ -69,8 +69,8 @@ class XmlExporter extends AbstractExporter
             $root->addAttribute('schema', $metadata->table['schema']);
         }
 
-        if (isset($metadata->table['inheritance-type'])) {
-            $root->addAttribute('inheritance-type', $metadata->table['inheritance-type']);
+        if ($metadata->inheritanceType && $metadata->inheritanceType !== ClassMetadataInfo::INHERITANCE_TYPE_NONE) {
+            $root->addAttribute('inheritance-type', $this->_getInheritanceTypeString($metadata->inheritanceType));
         }
 
         if ($metadata->discriminatorColumn) {