Client-side as follows:

var $inputEmail = $('.emailaddress input');
var $inputConfirmEmail = $('.confirmemailaddress input');
$inputConfirmEmail.attr('equalto', '#' +
$inputEmail.attr('id'));                                   
$('form').validate().settings.messages[$inputConfirmEmail.attr('id')].equalTo
= $inputConfirmEmail.attr('data-val-regex');

Server-side:

Are you using razor?

Easiest to do with code first: http://www.nibble.be/?p=205

If you don't have a code first form you can still hook into the server side validation there is an event available 

Umbraco.Forms.Mvc.Controllers.FormRenderController FormValidate

Hey Tim,
We are not using CodeFirst as the client will be creating many more forms so can't go down that road unfortunately.

So with the event do I just hook into it the FormValidate event in a class?
Also will it fire for all forms or just a specific form?

Cheers,
Warren :) 

Fires for all forms

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