diff --git a/library/HTMLPurifier/ConfigSchema/schema.ser b/library/HTMLPurifier/ConfigSchema/schema.ser
index 1e6ccd22..e47dab83 100644
Binary files a/library/HTMLPurifier/ConfigSchema/schema.ser and b/library/HTMLPurifier/ConfigSchema/schema.ser differ
diff --git a/library/HTMLPurifier/ConfigSchema/schema/URI.UnescapeCharacters.txt b/library/HTMLPurifier/ConfigSchema/schema/URI.UnescapeCharacters.txt
new file mode 100644
index 00000000..ce5e7e40
--- /dev/null
+++ b/library/HTMLPurifier/ConfigSchema/schema/URI.UnescapeCharacters.txt
@@ -0,0 +1,9 @@
+URI.UnescapeCharacters
+TYPE: string/null
+DEFAULT: NULL
+--DESCRIPTION--
+
+<p>
+    Defines characters that won't be escape by HTMLPurifier_URI.
+</p>
+--# vim: et sw=4 sts=4
\ No newline at end of file
diff --git a/library/HTMLPurifier/URI.php b/library/HTMLPurifier/URI.php
index a5e7ae29..d5fdfb9a 100644
--- a/library/HTMLPurifier/URI.php
+++ b/library/HTMLPurifier/URI.php
@@ -106,7 +106,7 @@ class HTMLPurifier_URI
     public function validate($config, $context)
     {
         // ABNF definitions from RFC 3986
-        $chars_sub_delims = '!$&\'()*+,;=';
+        $chars_sub_delims = '!$&\'()*+,;='.$config->get('URI.UnescapeCharacters');;
         $chars_gen_delims = ':/?#[]@';
         $chars_pchar = $chars_sub_delims . ':@';