Mail functionality is there, you unfortunately have to use the source tab since it is not in the components list yet and no properties pane. Mail functionality has improved btw.
The ESB node is not there since ESB support is 'two way' and because the ESB does not support jBPM 4 (yet) there is no need to have an ESB node in jpdl 4 and hence the GPD
Oh, and if you have added the xsd to eclipse you can see the attributes and child elements on the mail node. Also look at the examples