From the header comments of TikZ-UML
(obtained from http://www.ensta-paristech.fr/~kielbasi/tikzuml/index.php):

% Some macros for UML Diagrams.
% Home page of project: 
% Author: Nicolas Kielbasiewicz
% Style from: 
% Fixed by Nicolas Kielbasiewicz (nicolas.kielbasiewicz@ensta-paristech.fr) in dec 2010 to compile with pgf 2.00