On Mint 14 with Cinnamon, when I "CTRL C - V" a formula under Calc, I get a text (a drag and drop works but for adjancents cells). Sometime, "paste special" opens the normal windows or just "unformatted text".
I tested under the Gnome Session, no problem with the sames files.
I removed LO 3.6 and install the LO 4.0 beta 2 version and same behavior. I checked that "lo-menubar" wasn't installed (as it created such conflit more than one year ago).
I searched on internet and it seems there is no problem under Ubuntu and my test under Gnome could indicate there is a conflit between LO and Cinnamon.
Any idea ?