(First floor.) Ration of Food blocks the door. Mage pretty much starts with everything you need to solve that room.
Edit: This seed is crazy, already with artifact and wand on the first three floors. LBX-MZH-SYDv2.5.2 (Mage; On Diet&Faith Is My Armor&Forbidden Runes)
Though to be fair, you can almost always just step on the sheep traps without any danger. I love finding those rooms. Means I get a free levitation potion.
If you can't bare loosing some efficiency (you must be fun as a coder in a really big, multinational project) you can just throw a random item at the traps. You don't even loose one charge of the second worst wand of the game.