Do you keep your project code names the same in the source tree?

Do you keep your project code names the same in the source tree?

Sometimes when I start working on a project, I just can't think of a good
name, or think of a good name that isn't already taken. As a result, I'll
end up picking some sort of code name for the project.
My question is, how do you handle name changes in your source code once
you find a real name for your project? Should you continue to refer to the
code name in your source tree, namespaces, binaries, etc?