diff --git a/phpBB/includes/acp/acp_board.php b/phpBB/includes/acp/acp_board.php
index e018655407..59f7bf707f 100644
--- a/phpBB/includes/acp/acp_board.php
+++ b/phpBB/includes/acp/acp_board.php
@@ -57,7 +57,7 @@ class acp_board
 						'board_disable_msg'		=> false,
 						'default_lang'			=> array('lang' => 'DEFAULT_LANGUAGE',		'validate' => 'lang',	'type' => 'select', 'function' => 'language_select', 'params' => array('{CONFIG_VALUE}'), 'explain' => false),
 						'default_dateformat'	=> array('lang' => 'DEFAULT_DATE_FORMAT',	'validate' => 'string',	'type' => 'custom', 'method' => 'dateformat_select', 'explain' => true),
-						'board_timezone'		=> array('lang' => 'SYSTEM_TIMEZONE',		'validate' => 'string',	'type' => 'select', 'function' => 'tz_select', 'params' => array('{CONFIG_VALUE}', 1), 'explain' => true),
+						'board_timezone'		=> array('lang' => 'SYSTEM_TIMEZONE',		'validate' => 'timezone',	'type' => 'select', 'function' => 'tz_select', 'params' => array('{CONFIG_VALUE}', 1), 'explain' => true),
 						'default_style'			=> array('lang' => 'DEFAULT_STYLE',			'validate' => 'int',	'type' => 'select', 'function' => 'style_select', 'params' => array('{CONFIG_VALUE}', false), 'explain' => false),
 						'override_user_style'	=> array('lang' => 'OVERRIDE_STYLE',		'validate' => 'bool',	'type' => 'radio:yes_no', 'explain' => true),
 
@@ -908,7 +908,7 @@ class acp_board
 		$old_tz = $user->tz;
 		if (is_numeric($config['board_timezone']))
 		{
-			// Might still be numeric by chance
+			// Might still be numeric
 			$config['board_timezone'] = sprintf('Etc/GMT%+d', $config['board_timezone']);
 		}
 		$user->tz = new DateTimeZone($config['board_timezone']);