diff --git a/library/HTMLPurifier.includes.php b/library/HTMLPurifier.includes.php
index 97fcf27d..f4956fa4 100644
--- a/library/HTMLPurifier.includes.php
+++ b/library/HTMLPurifier.includes.php
@@ -138,6 +138,7 @@ require 'HTMLPurifier/ConfigSchema/Validator/Composite.php';
 require 'HTMLPurifier/ConfigSchema/Validator/Exists.php';
 require 'HTMLPurifier/ConfigSchema/Validator/NamespaceExists.php';
 require 'HTMLPurifier/ConfigSchema/Validator/Or.php';
+require 'HTMLPurifier/ConfigSchema/Validator/ParseDefault.php';
 require 'HTMLPurifier/ConfigSchema/Validator/ParseId.php';
 require 'HTMLPurifier/ConfigSchema/Validator/ParseType.php';
 require 'HTMLPurifier/ConfigSchema/Validator/Unique.php';
diff --git a/library/HTMLPurifier/ConfigSchema/Interchange.php b/library/HTMLPurifier/ConfigSchema/Interchange.php
index 76fa828f..31e28775 100644
--- a/library/HTMLPurifier/ConfigSchema/Interchange.php
+++ b/library/HTMLPurifier/ConfigSchema/Interchange.php
@@ -66,6 +66,7 @@ class HTMLPurifier_ConfigSchema_Interchange
         $directive->addValidator($this->make('Exists', '_TYPE'));
         $directive->addValidator($this->make('Exists', '_NULL'));
         $directive->addValidator($this->make('Exists', 'DEFAULT'));
+        $directive->addValidator($this->make('ParseDefault'));
         
         // Common tests
         $validator->addValidator($this->make('Exists', 'DESCRIPTION'));
diff --git a/library/HTMLPurifier/ConfigSchema/Validator/ParseDefault.php b/library/HTMLPurifier/ConfigSchema/Validator/ParseDefault.php
new file mode 100644
index 00000000..3f21e691
--- /dev/null
+++ b/library/HTMLPurifier/ConfigSchema/Validator/ParseDefault.php
@@ -0,0 +1,18 @@
+<?php
+
+/**
+ * Parses DEFAULT into _DEFAULT. Expects DEFAULT, _TYPE, _NULL and ID to exist.
+ */
+class HTMLPurifier_ConfigSchema_Validator_ParseDefault extends HTMLPurifier_ConfigSchema_Validator
+{
+    
+    public function validate(&$arr, $interchange) {
+        $parser = new HTMLPurifier_VarParser_Native(); // not configurable yet
+        try {
+            $arr['_DEFAULT'] = $parser->parse($arr['DEFAULT'], $arr['_TYPE'], $arr['_NULL']);
+        } catch (HTMLPurifier_VarParserException $e) {
+            throw new HTMLPurifier_ConfigSchema_Exception('Invalid type for default value in '. $arr['ID'] .': ' . $e->getMessage());
+        }
+    }
+    
+}
diff --git a/tests/HTMLPurifier/ConfigSchema/Validator/ParseDefaultTest.php b/tests/HTMLPurifier/ConfigSchema/Validator/ParseDefaultTest.php
new file mode 100644
index 00000000..87b0b290
--- /dev/null
+++ b/tests/HTMLPurifier/ConfigSchema/Validator/ParseDefaultTest.php
@@ -0,0 +1,34 @@
+<?php
+
+class HTMLPurifier_ConfigSchema_Validator_ParseDefaultTest extends HTMLPurifier_ConfigSchema_ValidatorHarness
+{
+    
+    public function testValidate() {
+        $arr = array(
+            'ID' => 'N.D',
+            'DEFAULT' => 'true',
+            '_TYPE' => 'bool',
+            '_NULL' => false,
+        );
+        $this->validator->validate($arr, $this->interchange);
+        $this->assertIdentical($arr, array(
+            'ID' => 'N.D',
+            'DEFAULT' => 'true',
+            '_TYPE' => 'bool',
+            '_NULL' => false,
+            '_DEFAULT' => true,
+        ));
+    }
+    
+    public function testValidateFail() {
+        $arr = array(
+            'ID' => 'N.D',
+            'DEFAULT' => '"asdf"',
+            '_TYPE' => 'int',
+            '_NULL' => true,
+        );
+        $this->expectSchemaException('Invalid type for default value in N.D: Expected type int, got string');
+        $this->validator->validate($arr, $this->interchange);
+    }
+    
+}