We have been trying to make a curl requested to login to a secure website from within PHP on Ubuntu 12.04. However, curl was hanging and responding with a nothing.
After much debugging, it turns out the curl was failing to negoitiate the correct ssl protocol to use. You can test if you have the same bug as follows. Open a terminal in Ubuntu
Try:
curl https://the.secure.website.com
If it fails then try setting the SSL version to 3.
curl -3 https://the.secure.website.com
If this goes then set the SSL version in your PHP script.
curl_setopt($ch, CURLOPT_SSLVERSION, 3);
Hope this helps someone.