Quote Originally Posted by Curmudgeon View Post
The DM is specifically allowed to disagree with magic device trap elements, and empowered to set the cost. From DMG page 74: If you don't like what the PC is trying to do with a magic device trap, simply don't agree to the spells or other elements. And the DM determines the cost and CR.
That language is not in the SRD. Nor do I believe it is in my first printing 3.5 DMG (not with my books).