Try to register custom constraints based on the type of the field. Uses the GrailsDomainClass.

ConstraintRegistrar.groovy

package br.com.insoft4.core.constraints

import org.codehaus.groovy.grails.commons.DefaultGrailsDomainClassProperty
import org.codehaus.groovy.grails.commons.GrailsDomainClass
import org.codehaus.groovy.grails.validation.ConstrainedProperty;

import br.com.insoft4.core.types.EmpresaIdentity;
import br.com.insoft4.core.types.SimNao


import grails.util.Holders

class ConstraintRegistrar {

  static void registerConstraints() {
		List<GrailsDomainClass> domainClasses = Holders.getGrailsApplication().getArtefacts("Domain")
		domainClasses.each ConstraintRegistrar.&registerConstraints
	}
	
	static void registerConstraints(Class clazz) {
		GrailsDomainClass domainClass = Holders.getGrailsApplication().getDomainClass(clazz.name)
		registerConstraints(domainClass)
	}
	
	static void registerConstraints( GrailsDomainClass domainClass ) {
		
		registerConstraint(domainClass, SimNao.class, SimNaoConstraint.CONSTRAINT_NAME)
		registerConstraint(domainClass, EmpresaIdentity.class, EmpresaIdentityConstraint.CONSTRAINT_NAME)
		
	}
	
	static void registerConstraint(GrailsDomainClass domainClass, Class type, String consName) {
		List<DefaultGrailsDomainClassProperty> props = domainClass.properties.findAll { type.isAssignableFrom( it.type ) }
		def constraints = domainClass.constraints
		for(DefaultGrailsDomainClassProperty prop : props) {
			String propName = prop.name
			ConstrainedProperty constraint = (constraints."$propName")
			if( !constraint.getAppliedConstraint(consName) ) {
				constraint.applyConstraint(consName, true)
			}
		}
	}
		
}