VCS Labeling

Why does this labeling pattern not work?

%system.teamcity.projectName% - %system.build.number%

My label ends up being created something like this: %system.teamcity.projectName% - 4.1.58-889
But I expect this: DEU - 4.1.58-889

Is build number the only variable supported? If so, I would LOVE to see this fixed for 4.0 (please).

Thanks,
Ray