Stupid noob question re: magic shields and the other hand

[Sly Frog]

Okay, I did a quick search for this, but didn't find an answer.

Let's say there is a unit that comes with a semi-decent weapon (e.g. bane blade). I create a magic shield, give it to him. No matter which hand I put it on, it gets rid of his weapon, and says he is now attacking with his fist.

Is there a way to give someone a shield and have them keep their original weapon?