The sync between Evolution calendar and the gnome-panel, (clock), is still missing, (2.24 & 2.26).
Can you fix it?
Here the same thing working in a random distro:http://img39.imageshack.us/img39/9097/captures.png
Maybe this can help, (found on gnome site):
Why are my events displayed in Evolution, but not in the gnome-panel clock applet?
If you compile yourself, make sure that gnome-panel is built with "USE=eds".