It is possible to add older SDKs to XCODE using older Xcode versions.

From a terminal:

open /Volumes/Xcode\ and\ iOS\ SDK/Packages/


Install pkg file into folder of choice, not in Applications/Xcode.app/Contents/Developer.

You’ll find the package installed in the Platforms folder in the volume you chose. Move the relevant SDK over to the Developer folder within Xcode.app. You’ll likely have to use sudo:


sudo mv /Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS4.3.sdk /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/