Comment 26 for bug 882307

Confirmed on 12.04 even after all updates. In my case is just easy to test it. There are 2 ways, one happens always, the other one happens in some cases:

Rare Nautilus Case (This happens rarely):

1. Go to nautilus and copy any file/folde you want.
2. Right click on an empty space and see that the Paste option in the context menu is grayed.

Note that it is selectible and you can paste, but to see it grayed I would thinks that I did not copy anything.

Desktop Case (Always happens. I mean ALWAYS!):

1. On your desktop copy anything there, be it a folder or a file.
2. Right click on an empty space and see that the Paste option in the context menu is grayed.

This might have something to do with the fact that Gnome3 removed files/folders from the Desktop. So in Unity maybe some option is not affecting the way a clipboard created from a Desktop object is detected and does not active the Paste option.