[Flow] array of objects and validators

[mario chiari]

Hi

I need some help with validators.
Say I have a basic Father/Son model, and a New template to create
several Fathers and theirs Sons at once. See at
http://pastebin.com/jJk2Aqb3 .

My createAction cycles over the array of Fathers and creates Father
objects by 
$fatherObj = $propertyMapper->convert($fthArray, '\...\Model\Father');

Now the question is, where and how do I validate? I have tried something
as you see in the pastebin, but it does not work.  

your flow-savy advise is welcome
mario