Version:           4.2.2 (using 4.2.2 (KDE 4.2.2), Debian packages)
Compiler:          cc
OS:                Linux (i686) release 2.6.29-2-686-bigmem

I have added some Google Calendars to the Akonadi service and imported these calendars from KOrganizer. I've set colors to each calendar and removed the color of the parent. when I closed and relaunch KOrganizer, two things happen:

1- Sibling calendars all lose their color in the sidebar but events show with true colors on the calendar display.

2- Parent grouper (The tree node that spans the calendars) becomes randomly colored.

How to reproduce:
1- Add some calendars to Akonadi (I use google calendars over remote iCAL files) via system settings.
2- Import these calendars to KOrganizer
3- Set color of each calendar by right clicking to resource and selecting Resource Colors -> Assign...
4- Close and re-open KOrganizer.
5- Siblings' colors have gone and parent got a random color. Hooray!

Notes:
0- You can re-set the colors but restart will reproduce the bug again. 1-Interestingly if you remove and re-add the calendars, sibling colors just show up OK.
2- When you try to re-set the colors of the siblings, the colors loaded in the color picker is the last color that you have set (i.e. correct color) for that calendar. 
3- If you set a color to the parent node, it reloads just OK.

Expected Behaviour:
Resource colors should be reloaded as saved. Siblings and parent should reflect the adjustments made in previous session (the session that the colors assigned / disabled)