diff --git a/classes/Kohana/Arr.php b/classes/Kohana/Arr.php
index 6bdfe59b2..bcd4735f7 100644
--- a/classes/Kohana/Arr.php
+++ b/classes/Kohana/Arr.php
@@ -282,7 +282,13 @@ public static function range($step = 10, $max = 100)
 	 */
 	public static function get($array, $key, $default = NULL)
 	{
-		return isset($array[$key]) ? $array[$key] : $default;
+		if ($array instanceof ArrayObject) {
+			// This is a workaround for inconsistent implementation of isset between PHP and HHVM
+			// See https://github.com/facebook/hhvm/issues/3437
+			return $array->offsetExists($key) ? $array->offsetGet($key) : $default;
+		} else {
+			return isset($array[$key]) ? $array[$key] : $default;
+		}
 	}
 
 	/**
diff --git a/classes/Kohana/Config/Group.php b/classes/Kohana/Config/Group.php
index 0460c898d..3e35fdf55 100644
--- a/classes/Kohana/Config/Group.php
+++ b/classes/Kohana/Config/Group.php
@@ -11,8 +11,8 @@
  * @package    Kohana
  * @category   Configuration
  * @author     Kohana Team
- * @copyright  (c) 2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2012-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_Config_Group extends ArrayObject {
 
diff --git a/classes/Kohana/Config/Source.php b/classes/Kohana/Config/Source.php
index cfce07609..388986085 100644
--- a/classes/Kohana/Config/Source.php
+++ b/classes/Kohana/Config/Source.php
@@ -7,8 +7,8 @@
  * @package    Kohana
  * @category   Configuration
  * @author     Kohana Team
- * @copyright  (c) 2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2012-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 
 interface Kohana_Config_Source {}
diff --git a/classes/Kohana/Config/Writer.php b/classes/Kohana/Config/Writer.php
index 3db22c037..856ebde8d 100644
--- a/classes/Kohana/Config/Writer.php
+++ b/classes/Kohana/Config/Writer.php
@@ -7,8 +7,8 @@
  *
  * @package Kohana
  * @author  Kohana Team
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 interface Kohana_Config_Writer extends Kohana_Config_Source
 {
diff --git a/classes/Kohana/Cookie.php b/classes/Kohana/Cookie.php
index dafb7f5a4..fe4cc490d 100644
--- a/classes/Kohana/Cookie.php
+++ b/classes/Kohana/Cookie.php
@@ -71,7 +71,7 @@ public static function get($key, $default = NULL)
 			// Separate the salt and the value
 			list ($hash, $value) = explode('~', $cookie, 2);
 
-			if (Cookie::salt($key, $value) === $hash)
+			if (Security::slow_equals(Cookie::salt($key, $value), $hash))
 			{
 				// Cookie signature is valid
 				return $value;
diff --git a/classes/Kohana/Date.php b/classes/Kohana/Date.php
index 692d658cb..930edc381 100644
--- a/classes/Kohana/Date.php
+++ b/classes/Kohana/Date.php
@@ -592,10 +592,10 @@ public static function formatted_time($datetime_str = 'now', $timestamp_format =
 		$tz   = new DateTimeZone($timezone ? $timezone : date_default_timezone_get());
 		$time = new DateTime($datetime_str, $tz);
 
-		if ($time->getTimeZone()->getName() !== $tz->getName())
-		{
-			$time->setTimeZone($tz);
-		}
+		// Convert the time back to the expected timezone if required (in case the datetime_str provided a timezone,
+		// offset or unix timestamp. This also ensures that the timezone reported by the object is correct on HHVM
+		// (see https://github.com/facebook/hhvm/issues/2302).
+		$time->setTimeZone($tz);
 
 		return $time->format($timestamp_format);
 	}
diff --git a/classes/Kohana/Debug.php b/classes/Kohana/Debug.php
index 2b1689e98..43fee91f0 100644
--- a/classes/Kohana/Debug.php
+++ b/classes/Kohana/Debug.php
@@ -5,8 +5,8 @@
  * @package    Kohana
  * @category   Base
  * @author     Kohana Team
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_Debug {
 
diff --git a/classes/Kohana/HTML.php b/classes/Kohana/HTML.php
index a95781303..b34363651 100644
--- a/classes/Kohana/HTML.php
+++ b/classes/Kohana/HTML.php
@@ -127,9 +127,9 @@ public static function anchor($uri, $title = NULL, array $attributes = NULL, $pr
 					$attributes['target'] = '_blank';
 				}
 			}
-			elseif ($uri[0] !== '#')
+			elseif ($uri[0] !== '#' AND $uri[0] !== '?')
 			{
-				// Make the URI absolute for non-id anchors
+				// Make the URI absolute for non-fragment and non-query anchors
 				$uri = URL::site($uri, $protocol, $index);
 			}
 		}
diff --git a/classes/Kohana/HTTP.php b/classes/Kohana/HTTP.php
index 083b43589..eca52c4e6 100644
--- a/classes/Kohana/HTTP.php
+++ b/classes/Kohana/HTTP.php
@@ -11,8 +11,8 @@
  * @category   HTTP
  * @author     Kohana Team
  * @since      3.1.0
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 abstract class Kohana_HTTP {
 
diff --git a/classes/Kohana/HTTP/Header.php b/classes/Kohana/HTTP/Header.php
index 6a35e9138..0debabf6c 100644
--- a/classes/Kohana/HTTP/Header.php
+++ b/classes/Kohana/HTTP/Header.php
@@ -9,8 +9,8 @@
  * @category   HTTP
  * @author     Kohana Team
  * @since      3.1.0
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_HTTP_Header extends ArrayObject {
 
diff --git a/classes/Kohana/HTTP/Message.php b/classes/Kohana/HTTP/Message.php
index 0861a733a..c24046ec1 100644
--- a/classes/Kohana/HTTP/Message.php
+++ b/classes/Kohana/HTTP/Message.php
@@ -7,8 +7,8 @@
  * @category   HTTP
  * @author     Kohana Team
  * @since      3.1.0
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 interface Kohana_HTTP_Message {
 
diff --git a/classes/Kohana/HTTP/Request.php b/classes/Kohana/HTTP/Request.php
index 8b2169c5f..b8992725f 100644
--- a/classes/Kohana/HTTP/Request.php
+++ b/classes/Kohana/HTTP/Request.php
@@ -8,8 +8,8 @@
  * @category   HTTP
  * @author     Kohana Team
  * @since      3.1.0
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 interface Kohana_HTTP_Request extends HTTP_Message {
 
diff --git a/classes/Kohana/HTTP/Response.php b/classes/Kohana/HTTP/Response.php
index 71058ac49..ddce6b4b9 100644
--- a/classes/Kohana/HTTP/Response.php
+++ b/classes/Kohana/HTTP/Response.php
@@ -8,8 +8,8 @@
  * @category   HTTP
  * @author     Kohana Team
  * @since      3.1.0
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 interface Kohana_HTTP_Response extends HTTP_Message {
 
diff --git a/classes/Kohana/Request.php b/classes/Kohana/Request.php
index ba7738548..bdc059ecf 100644
--- a/classes/Kohana/Request.php
+++ b/classes/Kohana/Request.php
@@ -740,7 +740,6 @@ public function uri($uri = NULL)
 	 *
 	 *     echo URL::site($this->request->uri(), $protocol);
 	 *
-	 * @param   array    $params    URI parameters
 	 * @param   mixed    $protocol  protocol string or Request object
 	 * @return  string
 	 * @since   3.0.7
diff --git a/classes/Kohana/Request/Client.php b/classes/Kohana/Request/Client.php
index 26b744240..3c35faf61 100644
--- a/classes/Kohana/Request/Client.php
+++ b/classes/Kohana/Request/Client.php
@@ -26,7 +26,7 @@ abstract class Kohana_Request_Client {
 	/**
 	 * @var  array  Headers to preserve when following a redirect
 	 */
-	protected $_follow_headers = array('Authorization');
+	protected $_follow_headers = array('authorization');
 
 	/**
 	 * @var  bool  Follow 302 redirect with original request method?
@@ -205,7 +205,7 @@ public function follow_headers($follow_headers = NULL)
 		if ($follow_headers === NULL)
 			return $this->_follow_headers;
 
-		$this->_follow_headers = $follow_headers;
+		$this->_follow_headers = array_map('strtolower', $follow_headers);
 
 		return $this;
 	}
@@ -405,10 +405,14 @@ public static function on_header_location(Request $request, Response $response,
 					break;
 			}
 
-			// Prepare the additional request
+			// Prepare the additional request, copying any follow_headers that were present on the original request
+			$orig_headers = $request->headers()->getArrayCopy();
+			$follow_header_keys = array_intersect(array_keys($orig_headers), $client->follow_headers());
+			$follow_headers = \Arr::extract($orig_headers, $follow_header_keys);
+
 			$follow_request = Request::factory($response->headers('Location'))
 			                         ->method($follow_method)
-			                         ->headers(Arr::extract($request->headers(), $client->follow_headers()));
+			                         ->headers($follow_headers);
 
 			if ($follow_method !== Request::GET)
 			{
diff --git a/classes/Kohana/Response.php b/classes/Kohana/Response.php
index 14e7938e1..04a47ee56 100644
--- a/classes/Kohana/Response.php
+++ b/classes/Kohana/Response.php
@@ -7,8 +7,8 @@
  * @package    Kohana
  * @category   Base
  * @author     Kohana Team
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  * @since      3.1.0
  */
 class Kohana_Response implements HTTP_Response {
diff --git a/classes/Kohana/Security.php b/classes/Kohana/Security.php
index b8f66c635..b07e499e4 100644
--- a/classes/Kohana/Security.php
+++ b/classes/Kohana/Security.php
@@ -81,8 +81,29 @@ public static function token($new = FALSE)
 	 */
 	public static function check($token)
 	{
-		return Security::token() === $token;
+		return Security::slow_equals(Security::token(), $token);
 	}
+	
+	
+	
+	/**
+	 * Compare two hashes in a time-invariant manner.
+	 * Prevents cryptographic side-channel attacks (timing attacks, specifically)
+	 * 
+	 * @param string $a cryptographic hash
+	 * @param string $b cryptographic hash
+	 * @return boolean
+	 */
+	public static function slow_equals($a, $b) 
+	{
+		$diff = strlen($a) ^ strlen($b);
+		for($i = 0; $i < strlen($a) AND $i < strlen($b); $i++)
+		{
+			$diff |= ord($a[$i]) ^ ord($b[$i]);
+		}
+		return $diff === 0; 
+	}
+
 
 	/**
 	 * Remove image tags from a string.
diff --git a/tests/kohana/Config/File/ReaderTest.php b/tests/kohana/Config/File/ReaderTest.php
index ab22d14ae..bfc755eda 100644
--- a/tests/kohana/Config/File/ReaderTest.php
+++ b/tests/kohana/Config/File/ReaderTest.php
@@ -10,8 +10,8 @@
  * @author     Kohana Team
  * @author     Jeremy Bush <contractfrombelow@gmail.com>
  * @author     Matt Button <matthew@sigswitch.com>
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_Config_File_ReaderTest extends Kohana_Unittest_TestCase {
 
diff --git a/tests/kohana/Config/GroupTest.php b/tests/kohana/Config/GroupTest.php
index 66fd05856..6222c8df6 100644
--- a/tests/kohana/Config/GroupTest.php
+++ b/tests/kohana/Config/GroupTest.php
@@ -10,8 +10,8 @@
  * @author     Kohana Team
  * @author     Jeremy Bush <contractfrombelow@gmail.com>
  * @author     Matt Button <matthew@sigswitch.com>
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_Config_GroupTest extends Kohana_Unittest_TestCase
 {
diff --git a/tests/kohana/DebugTest.php b/tests/kohana/DebugTest.php
index ba04799d9..ce9ae6e9a 100644
--- a/tests/kohana/DebugTest.php
+++ b/tests/kohana/DebugTest.php
@@ -13,8 +13,8 @@
  * @category   Tests
  * @author     Kohana Team
  * @author     Jeremy Bush <contractfrombelow@gmail.com>
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_DebugTest extends Unittest_TestCase
 {
diff --git a/tests/kohana/HTMLTest.php b/tests/kohana/HTMLTest.php
index 015a65da4..c4505bc40 100644
--- a/tests/kohana/HTMLTest.php
+++ b/tests/kohana/HTMLTest.php
@@ -223,6 +223,20 @@ public function test_style($expected, $file, array $attributes = NULL, $protocol
 	public function provider_anchor()
 	{
 		return array(
+			// a fragment-only anchor
+			array(
+				'<a href="#go-to-section-kohana">Kohana</a>',
+				array(),
+				'#go-to-section-kohana',
+				'Kohana',
+			),
+			// a query-only anchor
+			array(
+				'<a href="?cat=a">Category A</a>',
+				array(),
+				'?cat=a',
+				'Category A',
+			),
 			array(
 				'<a href="http://kohanaframework.org">Kohana</a>',
 				array(),
diff --git a/tests/kohana/Http/HeaderTest.php b/tests/kohana/Http/HeaderTest.php
index 0894b468e..8f241d3a5 100644
--- a/tests/kohana/Http/HeaderTest.php
+++ b/tests/kohana/Http/HeaderTest.php
@@ -11,8 +11,8 @@
  * @package    Kohana
  * @category   Tests
  * @author     Kohana Team
- * @copyright  (c) 2008-2012 Kohana Team
- * @license    http://kohanaphp.com/license
+ * @copyright  (c) 2008-2014 Kohana Team
+ * @license    http://kohanaframework.org/license
  */
 class Kohana_HTTP_HeaderTest extends Unittest_TestCase {
 
diff --git a/tests/kohana/request/ClientTest.php b/tests/kohana/request/ClientTest.php
index fffc1d5d3..9ad870297 100644
--- a/tests/kohana/request/ClientTest.php
+++ b/tests/kohana/request/ClientTest.php
@@ -175,6 +175,29 @@ public function test_follows_with_headers()
 		$this->assertFalse(isset($headers['x-not-in-follow']), 'X-Not-In-Follow should not be passed to next request');
 	}
 
+	/**
+	 * Tests that the follow_headers are only added to a redirect request if they were present in the original
+	 *
+	 * @ticket 4790
+	 */
+	public function test_follow_does_not_add_extra_headers()
+	{
+		$response = Request::factory(
+			            $this->_dummy_redirect_uri(301),
+			            array(
+			                 'follow' => TRUE,
+			                 'follow_headers' => array('Authorization')
+			            ))
+		            ->headers(array())
+		            ->execute();
+
+		$data = json_decode($response->body(),TRUE);
+		$headers = $data['rq_headers'];
+
+		$this->assertArrayNotHasKey('authorization', $headers, 'Empty headers should not be added when following redirects');
+	}
+
+
 	/**
 	 * Provider for test_follows_with_strict_method
 	 *