On the BobCares.com blog today, there's a quick new tutorial on getting libcURL implemented within your installation of PHP.
In this article, we'll see how to install or upgrade libcurl to a new version ( 7.15.3 ) and then integrate it to the PHP running in the server. Following steps were successfully tested on a Plesk 7.5 server running on RHEL-3.
It's basically a two step process (if all goes well) - downloading/compiling/installing the cURL libraries and application, and integrating it with PHP. If you're going to want to use secure connections with your installation, you'll also need to install the current certifying authorities for your setup.