Apple’s developer website only links to the latest version of Xcode, which requires Snow Leopard (Mac OS X 10.6).

If you’re still running Leopard (10.5), you need to go to this alternative developer website:

http://connect.apple.com/

Log in with your ADC credentials, click “Downloads”, then click “Developer Tools” in the right sidebar, and then search the page for “3.1.4″. You might also want to check the wikipedia list of xcode versions to see if 3.1.4 is still the latest version.

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