"Do Not Disturb" not working

Update (9/21/2012): The phone needs to be in locked mode to make use of this feature. Hope this helps.

Before go in to complaining here is how to schedule Do Not Disturb feature.

 → Go to Settings
 → open Notifications
 → Tap on Do Not Disturb
 → Toggle on Schedule
 → Choose a time range
 → Allow Call From No One
→ Update(9/21/2012): Lock the phone by pressing the button on the top

now call your iPhone from a different phone... if its working, its just me.