Strange behaviour when selecting icons on Desktop using the keyboard

[Giova84]

On my Desktop i have only 4 icons. Sometimes, when i take a screenshot, i have a max number of 5 or 6 icons. Ok. The 4 - always presents - icons (disks, home, docs and trash) are aligned using the CTRL key, and the extra icons aren't aligned (see the screenshot Icons_notaligned.png). When i want to select icons with keyboard (eg selecting the first icon and moving through icons with the down arrow) i am able to only select the aligned icons. The extra icon is not selectable, if is not aligned! And if i align these extra icons, i am able to select them, starting from another one (screenshot Icon_aligned).