Promotion Request create form submission validator

Hi.

I'm trying to add form submission validation for Promotion Request creation wizard. But it doesn't work.

So:

1) i have my own validator class ext.nikiet.validators.CreatePRValidator with implemented validateFormSubmission method
2) this class is registered in codebase/service.properties

wt.services/svc/default/com.ptc.core.ui.validation.UIComponentValidator/CreatePRValidation/null/0=ext.nikiet.validators.CreatePRValidator/duplicate

3) this validator is added to action in PromotionRequest-actions.xml

<action name="create" .... afterVK="CreatePRValidation">

But CreatePRValidator is not created, and its method validateFormSubmission is not invoked during promotion request creation.
In jcaDebug mode DefaultUIComponentValidator is displayed for wizard ok button.
What am i doing wrong?
Thanks.

ps: windchill version 11.0 M030-CPS05