Composer install error - requires ext_curl when it's actually enabled

I'm trying to install Facebook PHP SDK with Composer. This is what I get $ composer install Loading composer repositories with package information Installing dependencies (including require-dev) Your requirements could not be resolved to an installable set of packages. Problem 1 - Installation request for facebook/php-sdk dev-master -> satisfiable by facebook/php-sdk[dev-master]. - facebook/php-sdk dev-master requires ext-curl * -> the requested PHP extension curl is missing from your system. Problem is, I have curl extension enabled (uncommented in php.ini). When I run `phpinfo()`, it says it's enabled. Only clue I have is that when I run `$ php -m`, 'curl' line is missing but I don't know what to do about it. I have wamp 2.4 on Win8 and I'm running composer in cmd.exe.