libsoup2.4-dev 2.23.91-0ubuntu1 (amd64 binary) in ubuntu intrepid

 It was originally part of a SOAP (Simple Object Access Protocol)
 implementation called Soup, but the SOAP and non-SOAP parts have now been
 split into separate packages.
 .
 libsoup uses the Glib main loop and is designed to work well with GTK
 applications. This enables GNOME applications to access HTTP servers
 on the network in a completely asynchronous fashion, very similar to
 the Gtk+ programming model (a synchronous operation mode is also
 supported for those who want it).
 .
 Features:
  * Both asynchronous (GMainLoop and callback-based) and synchronous APIs
  * Automatically caches connections
  * SSL Support using GnuTLS
  * Proxy support, including authentication and SSL tunneling
  * Client support for Digest, NTLM, and Basic authentication
  * Server support for Digest and Basic authentication
  * Basic client-side SOAP and XML-RPC support
 .
 This package contains the development files.