JBoss Developer Studio comes with a tight integration with Rich Faces component framework. Rich Faces and Ajax4jsf in JBoss Tools Palette always exist, this palette is not dynamic and is not changed from file to file. JBoss Tools Palette supports only the last version of the Rich Faces components.
If you'd like to know the last version of Rich Faces component framework see JBoss RichFaces site.
After installing JBDS Rich Faces components as well as Ajax4jsf ones are already on the JBoss Tools Palette: