HTTP_Request2 provides cleaner API and pluggable Adapters:
- Socket adapter, based on old HTTP_Request code,
- Curl adapter, wraps around PHP's cURL extension,
- Mock adapter, to use for testing packages dependent on HTTP_Request2.

It supports POST requests with data and file uploads, basic and digest
authentication, cookies, managing cookies across requests, proxies, gzip and
deflate encodings, redirects, monitoring the request progress with Observers.