For all of us hunters who are changing our quivers to bags, there is a bug that is annoying, though far from fatal. It has an easy fix.
If you should happen to have a new bag made to replace your old quiver, you will notice that zoning, flightpaths, and logging in and out, will suddenly dump the contents of your "new" bag into your other bags, randomly.
It is an easy fix:
Un-equip the new bag, place it in your backpack.
Log out completely from the game.
Log-in to WoW.
Re-equip the new bag, place your items in it.
Problem fixed.
At least, this quick-fix worked for me.