In Beta 1z3, I received a spear from a goodie hut with my sovereign, but decided I wanted to give it to my courier (peasant equiped with a club and messenger kit).   I opened up the equipment tab with my sovereign and dragged the spear to my other unit on the cloth map.    The spear showed up on the other unit, but also stayed with the sovereign, but I couldn't equip it with either of them.   After hitting the turn button, it disapeared off my sovereign, but still could not be equipped by the courier.  

Now that I think of it, do I have to research up the warfare tree before my people can use spears?   It was pretty earlier, so that may have been part of the problem if that is true.

edit:   the characters were not next to each other, they were across the map (which is probably not the intended use also).