diff --git a/lib/Cake/Routing/Router.php b/lib/Cake/Routing/Router.php
index 2528db7ea..68d88b73a 100644
--- a/lib/Cake/Routing/Router.php
+++ b/lib/Cake/Routing/Router.php
@@ -945,9 +945,9 @@ class Router {
 		if (!empty($named)) {
 			foreach ($named as $name => $value) {
 				if (is_array($value)) {
-					$flattend = Hash::flatten($value, '][');
+					$flattend = Hash::flatten($value, '%5D%5B');
 					foreach ($flattend as $namedKey => $namedValue) {
-						$output .= '/' . $name . "[$namedKey]" . self::$_namedConfig['separator'] . rawurlencode($namedValue);
+						$output .= '/' . $name . "%5B{$namedKey}%5D" . self::$_namedConfig['separator'] . rawurlencode($namedValue);
 					}
 				} else {
 					$output .= '/' . $name . self::$_namedConfig['separator'] . rawurlencode($value);
diff --git a/lib/Cake/Test/Case/Routing/RouterTest.php b/lib/Cake/Test/Case/Routing/RouterTest.php
index c42285f45..b3c65dc56 100644
--- a/lib/Cake/Test/Case/Routing/RouterTest.php
+++ b/lib/Cake/Test/Case/Routing/RouterTest.php
@@ -484,7 +484,7 @@ class RouterTest extends CakeTestCase {
 		$result = Router::url(array('controller' => 'tests', 'pages' => array(
 			1, 2, 3
 		)));
-		$expected = '/tests/index/pages[0]:1/pages[1]:2/pages[2]:3';
+		$expected = '/tests/index/pages%5B0%5D:1/pages%5B1%5D:2/pages%5B2%5D:3';
 		$this->assertEquals($expected, $result);
 
 		$result = Router::url(array('controller' => 'tests',
@@ -496,7 +496,7 @@ class RouterTest extends CakeTestCase {
 				'three'
 			)
 		));
-		$expected = '/tests/index/pages[param1][0]:one/pages[param1][1]:two/pages[0]:three';
+		$expected = '/tests/index/pages%5Bparam1%5D%5B0%5D:one/pages%5Bparam1%5D%5B1%5D:two/pages%5B0%5D:three';
 		$this->assertEquals($expected, $result);
 
 		$result = Router::url(array('controller' => 'tests',
@@ -508,7 +508,7 @@ class RouterTest extends CakeTestCase {
 				'three'
 			)
 		));
-		$expected = '/tests/index/pages[param1][one]:1/pages[param1][two]:2/pages[0]:three';
+		$expected = '/tests/index/pages%5Bparam1%5D%5Bone%5D:1/pages%5Bparam1%5D%5Btwo%5D:2/pages%5B0%5D:three';
 		$this->assertEquals($expected, $result);
 
 		$result = Router::url(array('controller' => 'tests',
@@ -520,14 +520,14 @@ class RouterTest extends CakeTestCase {
 				'cool'
 			)
 		));
-		$expected = '/tests/index/super[nested][array]:awesome/super[nested][something]:else/super[0]:cool';
+		$expected = '/tests/index/super%5Bnested%5D%5Barray%5D:awesome/super%5Bnested%5D%5Bsomething%5D:else/super%5B0%5D:cool';
 		$this->assertEquals($expected, $result);
 
 		$result = Router::url(array('controller' => 'tests', 'namedParam' => array(
 			'keyed' => 'is an array',
 			'test'
 		)));
-		$expected = '/tests/index/namedParam[keyed]:is%20an%20array/namedParam[0]:test';
+		$expected = '/tests/index/namedParam%5Bkeyed%5D:is%20an%20array/namedParam%5B0%5D:test';
 		$this->assertEquals($expected, $result);
 	}