fillToZero does not color negative values when crossover point is 0
The problem that I have noticed is that in some cases fillToZero does not use the negative series color for the charts.
I've looked at this in more detail and it does not behave correctly when there's a y value with 0. Then I had a look at the code and it seems that it only checks when the axis is crossed to color the areas.
I've changed the condition in jquery.jqplot.js (line 4263, version 0.9.7r597) if (this._plotData[i] * this._plotData[i+1] < 0)
to if (this._plotData[i] * this._plotData[i+1] <= 0
and now it behaves correctly for my small example.
I'm attaching the example. Hope that helps,