diff --git a/phpBB/docs/CHANGELOG.html b/phpBB/docs/CHANGELOG.html
index 90ff74a2b1..69ae879ebb 100644
--- a/phpBB/docs/CHANGELOG.html
+++ b/phpBB/docs/CHANGELOG.html
@@ -92,7 +92,7 @@
 		<li>[Fix] Sorting by author or subject on viewtopic now preserves the order. (Bug #44875)</li>
 		<li>[Fix] Correctly determine writable status of files on Windows operating system. (Bug #39035)</li>
 		<li>[Feature] Backported 3.2 captcha plugins.</li>
-		<li>[Feature] Introduced new ACM plugins: null, memcache.</li>
+		<li>[Feature] Introduced new ACM plugins: null, memcache, APC.</li>
 	</ul>
 	<a name="v304"></a><h3>1.ii. Changes since 3.0.4</h3>
 
diff --git a/phpBB/includes/acm/acm_apc.php b/phpBB/includes/acm/acm_apc.php
new file mode 100644
index 0000000000..409854bc26
--- /dev/null
+++ b/phpBB/includes/acm/acm_apc.php
@@ -0,0 +1,63 @@
+<?php
+/**
+*
+* @package acm
+* @version $Id$
+* @copyright (c) 2005, 2009 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+// Include the abstract base
+if (!class_exists('acm_memory'))
+{
+	require("${phpbb_root_path}includes/acm/acm_memory.$phpEx");
+}
+
+/**
+* ACM for APC
+* @package acm
+*/
+class acm extends acm_memory
+{
+	function acm()
+	{
+		// Call the parent constructor
+		parent::acm_memory();
+	}
+
+	/**
+	* Purge cache data
+	*/
+	function purge()
+	{
+		apc_clear_cache('user');
+
+		parent::purge();
+	}
+
+	function read($var)
+	{
+		return apc_fetch($var);
+	}
+
+	function write($var, $data, $ttl = 2592000)
+	{
+		return apc_store($var, $data, $ttl);
+	}
+
+	function delete($var)
+	{
+		return apc_delete($var);
+	}
+}
+
+?>
\ No newline at end of file
diff --git a/phpBB/includes/acm/acm_memcache.php b/phpBB/includes/acm/acm_memcache.php
index 1fe9218104..4950738522 100644
--- a/phpBB/includes/acm/acm_memcache.php
+++ b/phpBB/includes/acm/acm_memcache.php
@@ -3,7 +3,7 @@
 *
 * @package acm
 * @version $Id$
-* @copyright (c) 2005 phpBB Group
+* @copyright (c) 2005, 2009 phpBB Group
 * @license http://opensource.org/licenses/gpl-license.php GNU Public License
 *
 */
@@ -26,6 +26,12 @@ if (!extension_loaded('memcache') || !defined('PHPBB_ACM_MEMCACHE_HOST'))
 	return;
 }
 
+// Include the abstract base
+if (!class_exists('acm_memory'))
+{
+	require("${phpbb_root_path}includes/acm/acm_memory.$phpEx");
+}
+
 if (!defined('PHPBB_ACM_MEMCACHE_PORT'))
 {
 	define('PHPBB_ACM_MEMCACHE_PORT', 11211);
@@ -40,379 +46,51 @@ if (!defined('PHPBB_ACM_MEMCACHE_COMPRESS'))
 * ACM for Memcached
 * @package acm
 */
-class acm
+class acm extends acm_memory
 {
-	var $vars = array();
-	var $is_modified = false;
-
-	var $sql_rowset = array();
-	var $sql_row_pointer = array();
-	var $cache_dir = '';
-
 	var $memcache;
 	var $flags = 0;
 
-	/**
-	* Set cache path
-	*/
 	function acm()
 	{
-		global $phpbb_root_path;
+		// Call the parent constructor
+		parent::acm_memory();
 
 		$this->memcache = new Memcache;
 		$this->memcache->connect(PHPBB_ACM_MEMCACHE_HOST, PHPBB_ACM_MEMCACHE_PORT);
 		$this->flags = (PHPBB_ACM_MEMCACHE_COMPRESS) ? MEMCACHE_COMPRESSED : 0;
-
-		$this->cache_dir = $phpbb_root_path . 'cache/';
 	}
 
-	/**
-	* Load global cache
-	*/
-	function load()
-	{
-		// grab the global cache
-		$this->vars = $this->memcache->get('global');
-
-		if ($this->vars !== false)
-		{
-			return true;
-		}
-
-		return false;
-	}
-
-	/**
-	* Unload cache object
-	*/
 	function unload()
 	{
-		$this->save();
-		unset($this->vars);
-		unset($this->sql_rowset);
-		unset($this->sql_row_pointer);
-
-		$this->vars = array();
-		$this->sql_rowset = array();
-		$this->sql_row_pointer = array();
+		parent::unload();
 
 		$this->memcache->close();
 	}
 
-	/**
-	* Save modified objects
-	*/
-	function save()
-	{
-		if (!$this->is_modified)
-		{
-			return;
-		}
-
-		$this->memcache->set('global', $this->vars, $this->flags, 2592000);
-
-		$this->is_modified = false;
-	}
-
-	/**
-	* Tidy cache
-	*/
-	function tidy()
-	{
-		// cache has auto GC, no need to have any code here :)
-
-		set_config('cache_last_gc', time(), true);
-	}
-
-	/**
-	* Get saved cache object
-	*/
-	function get($var_name)
-	{
-		if ($var_name[0] == '_')
-		{
-			return $this->memcache->get($var_name);
-		}
-		else
-		{
-			return ($this->_exists($var_name)) ? $this->vars[$var_name] : false;
-		}
-	}
-
-	/**
-	* Put data into cache
-	*/
-	function put($var_name, $var, $ttl = 2592000)
-	{
-		if ($var_name[0] == '_')
-		{
-			$this->memcache->set($var_name, $var, $this->flags, $ttl);
-		}
-		else
-		{
-			$this->vars[$var_name] = $var;
-			$this->is_modified = true;
-		}
-	}
-
 	/**
 	* Purge cache data
 	*/
 	function purge()
 	{
-		// Purge all phpbb cache files
-		$dir = @opendir($this->cache_dir);
-
-		if (!$dir)
-		{
-			return;
-		}
-
-		while (($entry = readdir($dir)) !== false)
-		{
-			if (strpos($entry, 'ctpl_') !== 0 && strpos($entry, 'tpl_') !== 0)
-			{
-				continue;
-			}
-
-			$this->remove_file($this->cache_dir . $entry);
-		}
-		closedir($dir);
-
 		$this->memcache->flush();
 
-		unset($this->vars);
-		unset($this->sql_rowset);
-		unset($this->sql_row_pointer);
-
-		$this->vars = array();
-		$this->sql_rowset = array();
-		$this->sql_row_pointer = array();
-
-		$this->is_modified = false;
+		parent::purge();
 	}
 
-
-	/**
-	* Destroy cache data
-	*/
-	function destroy($var_name, $table = '')
+	function read($var)
 	{
-		if ($var_name == 'sql' && !empty($table))
-		{
-			if (!is_array($table))
-			{
-				$table = array($table);
-			}
-
-			foreach ($table as $table_name)
-			{
-				// gives us the md5s that we want
-				$temp = $this->memcache->get('sql_' . $table_name);
-
-				if ($temp === false)
-				{
-					continue;
-				}
-
-				// delete each query ref
-				foreach ($temp as $md5_id => $void)
-				{
-					$this->memcache->delete('sql_' . $md5_id);
-				}
-
-				// delete the table ref
-				$this->memcache->delete('sql_' . $table_name);
-			}
-
-			return;
-		}
-
-		if (!$this->_exists($var_name))
-		{
-			return;
-		}
-
-		if ($var_name[0] == '_')
-		{
-			$this->memcache->delete($var_name);
-		}
-		else
-		{
-			$this->is_modified = true;
-			unset($this->vars[$var_name]);
-
-			// We save here to let the following cache hits succeed
-			$this->save();
-		}
+		return $this->memcache->get($var);
 	}
 
-	/**
-	* Check if a given cache entry exist
-	*/
-	function _exists($var_name)
+	function write($var, $data, $ttl = 2592000)
 	{
-		if ($var_name[0] == '_')
-		{
-			return true;
-		}
-		else
-		{
-			if (!sizeof($this->vars))
-			{
-				$this->load();
-			}
-
-			return isset($this->vars[$var_name]);
-		}
+		return $this->memcache->set($var, $data, $this->flags, $ttl);
 	}
 
-	/**
-	* Load cached sql query
-	*/
-	function sql_load($query)
+	function delete($var)
 	{
-		// Remove extra spaces and tabs
-		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
-		$query_id = sizeof($this->sql_rowset);
-
-		if (($result = $this->memcache->get('sql_' . md5($query))) === false)
-		{
-			return false;
-		}
-
-		$this->sql_rowset[$query_id] = $result;
-		$this->sql_row_pointer[$query_id] = 0;
-
-		return $query_id;
-	}
-
-	/**
-	* Save sql query
-	*/
-	function sql_save($query, &$query_result, $ttl)
-	{
-		global $db;
-
-		// Remove extra spaces and tabs
-		$query = preg_replace('/[\n\r\s\t]+/', ' ', $query);
-		$hash = md5($query);
-
-		// determine which tables this query belongs to
-		preg_match('/FROM \\(?(\\w+(?: \\w+)?(?:, ?\\w+(?: \\w+)?)*)\\)?/', $query, $regs);
-		$tables = array_map('trim', explode(',', $regs[1]));
-
-		foreach ($tables as $table_name)
-		{
-			if (($pos = strpos($table_name, ' ')) !== false)
-			{
-				$table_name = substr($table_name, 0, $pos);
-			}
-
-			$temp = $this->memcache->get('sql_' . $table_name);
-
-			if ($temp === false)
-			{
-				$temp = array();
-			}
-
-			$temp[$hash] = true;
-
-			$this->memcache->set('sql_' . $table_name, $temp, $this->flags, $ttl);
-		}
-
-		// store them in the right place
-		$query_id = sizeof($this->sql_rowset);
-		$this->sql_rowset[$query_id] = array();
-		$this->sql_row_pointer[$query_id] = 0;
-
-		while ($row = $db->sql_fetchrow($query_result))
-		{
-			$this->sql_rowset[$query_id][] = $row;
-		}
-		$db->sql_freeresult($query_result);
-
-		$this->memcache->set('sql_' . $hash, $this->sql_rowset[$query_id], $this->flags, $ttl);
-
-		$query_result = $query_id;
-	}
-
-	/**
-	* Ceck if a given sql query exist in cache
-	*/
-	function sql_exists($query_id)
-	{
-		return isset($this->sql_rowset[$query_id]);
-	}
-
-	/**
-	* Fetch row from cache (database)
-	*/
-	function sql_fetchrow($query_id)
-	{
-		if ($this->sql_row_pointer[$query_id] < sizeof($this->sql_rowset[$query_id]))
-		{
-			return $this->sql_rowset[$query_id][$this->sql_row_pointer[$query_id]++];
-		}
-
-		return false;
-	}
-
-	/**
-	* Fetch a field from the current row of a cached database result (database)
-	*/
-	function sql_fetchfield($query_id, $field)
-	{
-		if ($this->sql_row_pointer[$query_id] < sizeof($this->sql_rowset[$query_id]))
-		{
-			return (isset($this->sql_rowset[$query_id][$this->sql_row_pointer[$query_id]][$field])) ? $this->sql_rowset[$query_id][$this->sql_row_pointer[$query_id]][$field] : false;
-		}
-
-		return false;
-	}
-
-	/**
-	* Seek a specific row in an a cached database result (database)
-	*/
-	function sql_rowseek($rownum, $query_id)
-	{
-		if ($rownum >= sizeof($this->sql_rowset[$query_id]))
-		{
-			return false;
-		}
-
-		$this->sql_row_pointer[$query_id] = $rownum;
-		return true;
-	}
-
-	/**
-	* Free memory used for a cached database result (database)
-	*/
-	function sql_freeresult($query_id)
-	{
-		if (!isset($this->sql_rowset[$query_id]))
-		{
-			return false;
-		}
-
-		unset($this->sql_rowset[$query_id]);
-		unset($this->sql_row_pointer[$query_id]);
-
-		return true;
-	}
-
-	/**
-	* Removes/unlinks file
-	*/
-	function remove_file($filename, $check = false)
-	{
-		if ($check && !@is_writable($this->cache_dir))
-		{
-			// E_USER_ERROR - not using language entry - intended.
-			trigger_error('Unable to remove files within ' . $this->cache_dir . '. Please check directory permissions.', E_USER_ERROR);
-		}
-
-		return @unlink($filename);
+		return $this->memcache->delete($var);
 	}
 }