Libjingle, the Google Talk Voice and P2P Interoperability Library,
is a set of components we provide to interoperate with Google
Talk's peer-to-peer file sharing and voice calling capabilities. The
package includes source code for Google's implementation of Jingle
and Jingle-Audio, two proposed extensions to the XMPP standard that
are currently available in draft form.

This requires speex, ortp, and ilbc.