Using JSF and AJAX with Ajax–enabled JSF implementations Ajax4Jsf,RichFaces,IceFaces

JBoss Ajax4jsf :
Ajax4jsf is an open source framework that adds AJAX capability into existing JSF applications without resorting to JavaScript.
Ajax4jsf leverages JavaServer Faces framework including lifecycle, validation, conversion facilities and management of static and dynamic resources. Ajax4jsf rich components with built-in AJAX support and a highly customizable look-and-feel can be easily incorporated into JSF applications.
http://labs.jboss.com/jbossajax4jsf/
JBoss RichFaces:
RichFaces is a rich component library for JSF built on top of Ajax4jsf, an advanced framework for easily integrating AJAX capabilities into business application development. The RichFaces components come ready to use out-of-the-box, so developers can immediately save time in taking advantage of component features to create Web applications that provide a greatly improved user experience more reliably and more quickly. RichFaces also includes strong support for the skinnability of JSF applications.
http://labs.jboss.com/jbossrichfaces/
ICEfaces :
ICEfaces is an integrated Ajax application framework that enables Java EE application developers to easily create and deploy thin-client rich Internet applications (RIA) in pure Java. ICEfaces is a fully featured product that enterprise developers can use to develop new or existing Java EE applications at no cost.
ICEfaces is the only RIA framework on the market today that delivers unique Ajax Push capabilities. Discover the power of Ajax Push and create collaborative and dynamic enterprise applications like never before.
ICEfaces leverages the entire standards-based Java EE ecosystem of tools and execution environments. Rich enterprise application features are developed in pure Java, and in a pure thin-client model. There are no Applets or proprietary browser plug-ins required. ICEfaces applications are JavaServer Faces (JSF) applications, so Java EE application development skills apply directly and Java developers are isolated from doing any JavaScript related development.
Product Benefits
The benefits of using ICEfaces to enrich enterprise web applications are numerous:
· Create a superior user experience and produce more effective enterprise Java EE applications
· Discover the unique power of Ajax Push
· Stay Java EE standards-compliant, develop in Java, not JavaScript
· Deploy securely across clustered servers
· Minimize total cost of ownership with Thin Client Ajax
· Transform the user experience

http://www.icefaces.org/main/home/index.jsp

Using JSF and AJAX with Ajax–enabled JSF implementations Article
http://www.javabeat.net/articles/jsf/2007/07/jsf-and-ajax-with-ajax-enabled-jsf-implementations/