SimpleHistogramDataset - Problem: HistogramType

[JFreeChartUser]

Hi,
is it possible to set the HistogramType of SimpleHistogramDataset to
RELATIVE_FREQUENCY like for HistogramDataset?!
When not, how can i set the range axis to display this information?
I know, i can use the HistogramDataset, but for my problem the HistogramDataset is not very usefull, because the bin for the origin x=0,y=0 is NEVER in the middle. I don't know why!

[rolf_rodenbach]

Bumping this... I need to specify my bins manually, so HistogramDataset is no good to me. But I do want to plot the relative frequencies

[Traxer]

I have excactly the same problem as JFreeChartUser! Any solutions?