Validating datetime fields in asp.net

I have three AJAX calendar controls (start date, end date and effective date) for in my project. Which selects date in the format dd/MM/yyyy hh:mm:ss tt. I want to add a following client side validations :

1. end date should be greater than or equal to start date.


2. effective date should be greater than end date.

I have tried using CompareValidator but it did not help as it do not allow me to compare time.

Is there any workaround to achieve this validation on client side.