Vibrating dialer buttons

[maczealot#WP]

I have a Sprint Touch Pro. At some point I changed this setting that makes it vibrate when I dial numbers on the on screen dial pad instead of the usual tones. Now I can't figure out how to change it back. I've gone through every single settings screen in my phone and can't find anything that mentions it. Where did I find that setting and how do I change it back?