Having problems with the control panel on localized site using MAMP

I have just set up a brand new version of EE locally on my mac using instructions from http://blog-en.mamp.info/2009/09/how-to-install-expressionengine-on-mamp.html . Basically my problem is anytime I try and access Admin>General Configuration (or anything on the admin tab) I get a fatal error saying:

“Fatal error: Uncaught Error: [] operator not supported for strings in /Users/user/Documents/Websites/ExpressionEngine/system/expressionengine/core/EE_Config.php:1574 Stack trace: #0 /Users/user/Documents/Websites/ExpressionEngine/system/expressionengine/controllers/cp/admin_system.php(199): EE_Config->prep_view_vars(‘general_cfg’) #1 /Users/user/Documents/Websites/ExpressionEngine/system/expressionengine/controllers/cp/admin_system.php(80): Admin_system->_config_manager(‘general_cfg’, ‘general_configu…’) #2 /Users/user/Documents/Websites/ExpressionEngine/system/codeigniter/system/core/CodeIgniter.php(329): Admin_system->general_configuration() #3 /Users/user/Documents/Websites/ExpressionEngine/admin.php(189): require_once(‘/Users/user/Doc…’) #4 {main} thrown in /Users/user/Documents/Websites/ExpressionEngine/system/expressionengine/core/EE_Config.php on line 1574”

I have looked for hours on end to solve this problem but nothing seems to work. Does anyone have any clue on how I can fix this?