Thanks for the answer.
As far as I understand you would have to use a template to show one of those charts in habpanel.
I was curious if the native chart widget is customisable at all. The string at right ( presented by rrd4j) hints it would be.
I'm happy so far with using the rrd4j database and would like to stick with it.
As usual I scanned the whole reply, b that I missed this two letter word at the beginning. Got it.