Install Mac OS X 10.6 SDK on newer Xcode

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