build version - iphone app (xcode)

For one of my applications in xcode, I have the option to build for m开发者_如何学编程any different versions ranging from 3.0 to 3.1.3.

Now when I make a new application, I only have the option to build this new application for 3.1.3. I can't seem to find where this project setting is.

How can I build my application for 3.0?

Thanks.

High-light the project name in XCode > Info > Build > Base SDK

You have to make sure you have it installed I believe. When you perform the install, there are options, and a bunch of them are for the different versions to install.