title: iPhone OS Deployment Target after update to iPhone SDK 4
body: <p>I just updated to iPhone SDK 4 and am trying to debug on my device with 3.1.3 installed. Before the update, I compiled with Base and Active SDK set to 3.1.3 and all was well. <em>After</em> the update, I'm limited to SDKs 4.0 and 3.2--setting the base to 4.0 and iPhone OS Deployment Target to iPhone OS 3.1.3, I'm able to build and install on my 3.1.3 device, but receive the following error:</p>
  
  <blockquote>
    <p>Error from Debugger: mi_cmd_stack_list_frames: Not enough frames in stack</p>
  </blockquote>
  
  <p>I'm not using anything specific to the newer SDK, as I haven't touched a bit of code, just updated the SDK/XCode. So what am I doing incorrectly? The application runs as expected on an iOS4-installed device. Are there changes to pre-existing API's that need to be weakly linked perhaps? Thanks for all help. </p>