zedgraph order values desc

[ucu13]

Hello,
I want to order the x axis to show from the newer date to old one.

exemple:
now show: 05.08.2012-> 06.08.2012->07.08.2012 on x axix

i want to show: 07.08.2012->06.08.2012->05.08.2012 on x axis

some ideas pls