• Go to https://developer.apple.com/downloads/index.action and download Xcode 4.3.3
  • After downloading mount the DMG file and navigate to Xcode.app
  • Open the application by clicking Show Package Content
  • Navigate to /Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs
  • Copy the MacOSX10.6.sdk folder
  • Navigate to /Applications/XCode.app and click Show Package Content
  • Navigate to /Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs
  • Paste the copied MacOSX10.6.sdk folder
  • Restart Xcode

Mac OS X 10.6 SDK should now be available for selection and building.

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