Namespace name bug, or am I doing something wrong?

I'm a novice PHP programmer and just recently starting learning about an implementing namespaces in my application. For several namespaces I am using, PhpStorm shows the error/warning "undefined constant [namespacename]", but it seems kind of inconsistant. Here's a video:

http://screencast.com/t/6rJjvHDjn

When you click on the video, just let it play and the stupid bar covering it up will go away.

Am I doing something wrong, or is this a bug?

Thanks!