When you equip different Loadouts while viewing the Equipment tab in the Character dialog, the selected weapon slot changes magically. Sometimes a sword is mistaken for a gun, too. This leads to the Character holding the sword upwards like a gun.
I have taken some screenshots:
http://img849.imageshack.us/img849/7751/bug01e.png
http://img853.imageshack.us/img853/6306/bug02.png

I have to admit, that a sword held like that is just cosmetic and looks cool, too. However, the switching of the selected weapon is probably a real minor bug. If you cycle through the Loadouts, equipping different sets, the selected weapon slot changes from 1 to 4 or so.