jQuery UI datepicker, "disabled days" not working in IE 7 and 8

I use the following function to disable days from 2011-02-13 to 2011-02-18 in the date picker calendar:

function no_disabled_days(date){
               dateStr1 = '2011-02-13T00:00:00';                   
               dateStr2= '2011-02-18T00:00:00';

               disabled_start_day = new Date(dateS开发者_开发知识库tr1);
               disabled_end_day = new Date(dateStr2);

               if(date >= disabled_start_day && date <= disabled_end_day){
                   return [false];
               }


             return [true];

  }

$("#reserve_date").datepicker({
            beforeShowDay: no_disabled_Days
});

For example, if dateStr1='2011-02-13T00:00:00', dateStr2='2011-02-18T00:00:00', the days from 2011-02-13 to 2011-02-18 are disabled.

Things are working fine in Chrome and Firfox browswer, however, when I test in IE 7 and 8, things are not working, only datepicker calendar can popup, the disabled_days is not disabled. Why? How to change my code to let it also working in IE 7 and 8?

By the way, the 'T00:00:00' string is needed to resolve local timezone issue in Firefox,( to make the disable days working in Firefox), check out my other post here

---

the problem in IE is your format...

try this

alert(new Date('2011-02-13T00:00:00').getDate()); // alerts NaN, your current format
alert(new Date('2011/02/13T00:00:00').getDate()); // alerts 13
alert(new Date('02-13-2011T00:00:00').getDate()); // alerts 13

_{tested on IE 7}