title: Running 3.1.x iPhone Simulator after upgrading to 3.2.4
body: <p>I have an app that I want to distribute to 3.1.x devices, but I don't have a device to test on. I ran the app on another dev's 3.1 device, and it crashes, so I definitely have some debugging to do. Rather than find and buy an old 3.x device, I'd like to run a 3.1.x Simulator.</p>
  
  <p>Is there any way to do that?</p>
  
  <p>I have upgraded my XCode install to 3.2.4, and now I no longer have the old XCode installs. It seems that the solution is to have both the new developer package AND the old package installed side-by-side. But I can't find where to download the old package, and the proper install procedure, or if there's another way to test on 3.1.x.</p>