MVC :: Dynamic Client-Side Validation?

I have number of fields in the view, which I am dynamically showing/hiding on the client side using jQuery e.g, if user enter 'abc' in first field, I will show three more fields and if he enters 'xyz' then I will show only single field.

I am using data annotations based Asp.Net MVC 2 validation (MVC 2 RTM) and the requirement is that only visible fields should be validated. I have added some code on the server side and the partial validation is working fine there but the issue is on the client side. Actually it works fine first time but fails after wards.

Here is what I am doing:

In $(document).ready event I am popping all the validation stuff in the array as shown below:

for (i = 0; i < numOfFields; i++) {
fValidationArrL[i] = window.mvcClientValidationMetadata[0].Fields.pop();
}

When I show/hide the fields I push only those fields which are visible like this:

window.mvcClientValidationMetadata[0].Fields.push(fValidationArr[i]);

Th I run below two statements to refresh the stuff:

Sys.Application.remove_load(arguments.callee);
Sys.Mvc.FormContext._Application_Load();

It works fine first time but second time when I do show/hide again, it appends the validation list instead of replacing it. So at the end it will validate all the fields that I have shown to the user at some point of time.