dear richfaces developers,
I have seen a component from java/blueprints using google-maps for jsf https://blueprints.dev.java.net/complib/v2/map-viewer.html
<ui:mapViewer id="mapViewerx" center="#{MapBean.mapPoint}" info="#{MapBean.mapMarker}" markers="#{MapBean.locations}" style="height: 500px; width: 700px"/>
it depends what your "extend" means. Google Map API is much and much richer than setting marker and info. So, for me, the right term here is "limitations".