Upgrading SA from 1.9.6 to 2.0.4 - validation

[Matt]

Validation seems to have changed. I'm getting an error on an Id property "Validation type names in unobtrusive client validation rules must be unique. The following validation type was seen more than once: number". 

Looking at the Global.asax in the Northwind example there is the following new line which doesn't seem to have any effect on the error....

DataAnnotationsModelValidatorProvider.AddImplicitRequiredAttributeForValueTypes = false;

And the NHibernateValidatorProvider has been removed. In the WhoCanHelpMe application there's a line...

ModelValidatorProviders.Providers.Add(new ClientDataTypeModelValidatorProvider());

Can anyone explain why the two example projects differ in this way and what is best to use in SA 2.0.4 please?

Thanks

Matt