ASP.NET MVC Custom Client Validation

Implement IClientValidatable
Implement a jQuery validation method
Implement an unobtrusive adapter

public class GreaterThanDateAttribute : ValidationAttribute, IClientValidatable
{
...
public IEnumerable<ModelClientValidationRule> GetClientValidationRules(
ModelMetadata metadata, ControllerContext context)
{
var rule  = new ModelClientValidationRule();
rule.ErrorMessage = FormatErrorMessage(metadata.GetDisplayName());
rule.ValidationType = "greater";
rule.ValidationParameters.Add("other", otherPropertyName);
yield return rule;
}

customvalidation.js
/// <reference path="jquery-1.4.4-vsdoc.js" />
/// <reference path="jquery.validate-vsdoc.js" />
/// <reference path="jquery.validate.unobtrusive.js" />

jQuery.validator.addMethod("greater", function(value, element, param)
{
return Date.parse(value) > Date.parse($(param).val());
});

jQuery.validator.unobtrusive.adapters.add("greater", ["other"], function(options){
options.rules["greater"] = "#" + options.params.other;
options.messages["greater"] = options.message;                    // ~ rule.ErrorMessage
});

Generated html output
<input class="text-box-single-line" id="EndDate" name="EndDate" type="text" value="1/1/2010 12:00:00 AM"
data-val="true"
data-val-greater="EndDate must be greater than StartDate"
data-val-greater-other="StartDate"
/>