How to show popup window on validation event ?

Hi,
I'm stuck trying to find a good solution for my issue.
Can anyone tell me how to How to show popup window on validation event of a Date.I am using jQuery validation plug-in 1.6 for validation (jquery.validate.js). My scenario is like when user select a date its validate that date and shows proper error message if not valid.after that i want a popup window for password to make that invalid date to valid.
Unfortunatelly, I couldn't find any good solution for this.
Plz help me out.