diff --git a/NEWS b/NEWS
index 4dffe14f..33a0a335 100644
--- a/NEWS
+++ b/NEWS
@@ -31,6 +31,8 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
 - Throw error when %Core.Encoding is set to a spurious value. Previously,
   this errored silently and returned false.
 - Redirected stderr to stdout for flush error output.
+- %URI.DisableExternal will now use the host in %URI.Base if %URI.Host is not
+  available.
 . Strategy_MakeWellFormed now operates in-place, saving memory and allowing
   for more interesting filter-backtracking
 . New HTMLPurifier_Injector->rewind() functionality, allows injectors to rewind
diff --git a/library/HTMLPurifier/URIFilter/DisableExternal.php b/library/HTMLPurifier/URIFilter/DisableExternal.php
index d48bce06..960e2b9b 100644
--- a/library/HTMLPurifier/URIFilter/DisableExternal.php
+++ b/library/HTMLPurifier/URIFilter/DisableExternal.php
@@ -5,7 +5,7 @@ class HTMLPurifier_URIFilter_DisableExternal extends HTMLPurifier_URIFilter
     public $name = 'DisableExternal';
     protected $ourHostParts = false;
     public function prepare($config) {
-        $our_host = $config->get('URI', 'Host');
+        $our_host = $config->getDefinition('URI')->host;
         if ($our_host !== null) $this->ourHostParts = array_reverse(explode('.', $our_host));
     }
     public function filter(&$uri, $config, $context) {
diff --git a/tests/HTMLPurifier/URIFilter/DisableExternalTest.php b/tests/HTMLPurifier/URIFilter/DisableExternalTest.php
index e4559f48..b2319184 100644
--- a/tests/HTMLPurifier/URIFilter/DisableExternalTest.php
+++ b/tests/HTMLPurifier/URIFilter/DisableExternalTest.php
@@ -41,4 +41,11 @@ class HTMLPurifier_URIFilter_DisableExternalTest extends HTMLPurifier_URIFilterH
         );
     }
     
+    function testBaseAsHost() {
+        $this->config->set('URI', 'Base', 'http://www.example.com/foo/bar');
+        $this->assertFiltering(
+            'http://www.example.com/baz'
+        );
+    }
+    
 }