Jquery form validator - how can one check that a date is past a date in another field?

I'm building a form in which I have a start date and an end date field. I'm planning on using jQuery UI datepicke开发者_运维技巧r and jquery validationEngine scripts. The problem I have, besides from being a beginner in jQuery, is that I'm not sure how to prevent the user from entering an end date that is before the start date.

The validation engine I'm using is: http://www.position-absolute.com/articles/jquery-form-validator-because-form-validation-is-a-mess/

Thanks in advance

see this thread in regard to same question