This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
I'm not an expert in grails, but I think your problem is on the extending
the import will ignore any constraints in the source class (Person) that don't have corresponding properties in the importing classes. I know they are extended from Person, but how are you applying this rule in the extended classes on this constraint.
Hope That helps or gets you steered toward the correct answer.
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