Im running virtual box 4.3 on ubuntu 13.10, everything goes fine with windows guests but for Mac osx (Mountain Lyon) I just cant find how to install Guest additions. Seems like there's no osx installer in the iso. thanks in advance-
You're right, VirtualBox doesn't have guest additions for OSX. https://www.virtualbox.org/wiki/Guest_OSes
They only list Mac OSX Server (Leopard, Snow Leopard) under Mac and even that doesn't have guest additions.
It has something to do with licensing restrictions: