X-Axis category names are plotted to wrong position if irregular intervals are being used

[ssaarinen]

This is demonstrated by the below fiddle:
http://jsfiddle.net/HhuDr/

where "point 2" is rendered on x = 1 instead of x = 2 as specified by data point.

[eolsson]

Looks like a bug. Here is a workaround that you could try: http://jsfiddle.net/HhuDr/1/ its using the categories option instead of point names.