Setting a linechartdataset as a cubic line breaks line color array property

If you have a line chart data set and set the color array, each line segment will have a different color if you are using ChartColorTemplates.vordiplom;
This seems to only work if the line is not a cubic line. When the linechartdataset is a cubic line, colors doesn't work and only one color shows up for the whole line.
In the screenshot below, the first line is a noncubic line with colors changing and the second is a cubic line with only one solid color.

LineChartDataSet *set1 = [[LineChartDataSet alloc] initWithYVals:value label:@"text"];
set1.colors = ChartColorTemplates.vordiplom;