The alternative is to use this method. Doesn't lock, but there is no way to know its there. Holds a lot more than you would think:
http://www.elisetalk.com/forums/showthread.php?t=17329
We bought the car from the person who performed the mod, but it isn't difficult at all to perform. We have a 60GB older generation Ipod, wrapped in bubble wrap in there, along with all our driving documentation. Works like a charm and nothing rattles around like it might in a glovebox.