Open source metamodels of the rules and concepts described in Steve and Marc's book are available at miuml.org
with indepth and correct support of identifier and referential constraints.
As a consequence of this effort, my copy of their excellent book is well worn and coffee stained.
(Many of you already know about this from the LinkedIn Executable UML group and my twitter feed: twitter.com/Leon_Starr )
Feel free to download, discuss, use as training examples, build supporting tools, adapt to existing tools or just tell your friends at the next holiday party.
miuml.org
Hope to see you there.
- Leon