Download this file, open SuperOneClick, plug in your phone with USB debugging enabled, and hit the button. Let me know what happens (and if sideloading works). You won't see a menu option in the settings. Thanks!
Wish I can confirm, read about it and it should work because works for the Desire HD, basically the same phone, will give it a try tomorrow, if it doesn't work, I can bring back my Inspire to stock.
Will report back, wish me luck .