Add different Colors to Calendar Overlay Settings color

Dear All,

         I'm trying to show events on a calendar with different colors. The events are categorized based on Status field of

       Calendar list and I have two statuses. 1. Confirmed 2. Planning.

        When I create calendar overlays for two statues I'm only getting following colors.

        Dark Teal, Dark Blue, Dark Green, Olive Green, Red, Dark Purple Brown.   

 Can you please tell me how can I add some more different colors like yellow, sky blue to this drop down list.

        I referred this article http://davidlozzi.com/2012/01/26/color-code-your-sharepoint-calendar/

Thanks,

Dilip