The HttpResponse class requires at least PHP v5.1. Any other class is available as of PHP v5.0.
Nota: Be aware though, that some methods are not available with PHP v5.0.
In order to be able to load this extension on Windows, you additionally need to load the following PHP extensions: hash, iconv and SPL.
The extension must be built with » libcurl support to enable request functionality (--with-http-curl-requests). A library version equal or greater to v7.12.3 is required.
To enable support for sending and receiving compressed responses, the extension must be built with » zlib support (--with-http-zlib-compression). A library version equal or greater than v1.2.2 is required.
Content type guessing can be enabled by building this extension with » libmagic support (--with-http-magic-mime).