Please everyone, stop setting CURLOPT_SSL_VERIFYPEER to false or 0. If your PHP installation doesn't have an up-to-date CA root certificate bundle, download the one at the curl website and save it on your server:
http://curl.haxx.se/docs/caextract.html
Then set a path to it in your php.ini file, e.g. on Windows:
curl.cainfo=c:\php\cacert.pem
Turning off CURLOPT_SSL_VERIFYPEER allows man in the middle (MITM) attacks, which you don't want!