Hmm...seems to be a question for offical staff members. Here a fast unauthorized answer ;-)
1.) Ajax4JSF is completely integrated in Richfaces. On the basis of my experiences it is backwards compliant so you can use your old code.
2.) You only need the three richfaces jars of a version you want.
3.) If there are any: delete old richfaces/ajax4jsf libraries from your library-folder(s)
4.) Please read documentation or see richfaces demo.
Sweet! I'll give it a try. Thanks for the information ...