title: Valid input not recognized by IE 11
body: <p>I have an input element on my form that accepts a date/time. It has validation to check that it's a valid date/time. The default value for the field is the current date and time. When using Chrome, I can change the value of this input box multiple times, and as long as it is a valid date and time it will be accepted. However, in IE 11, if I change it to another valid date/time, it indicates an invalid value and will not allow the form to save. </p>
  
  <p>The date/time field:</p>
  
  <pre><code>input#transit_date_arrived.form-control.date-time-picker(name='transit_date_arrived', ng-model='vehicle.transit_date_arrived', type='datetime')
  </code></pre>
  
  <p>In the vehicle model:</p>
  
  <pre><code>transit_date_arrived: {
              type: sequelize.DATE,
              allowNull: true,
              validate: {
                  isDate: true
              }
          },
  </code></pre>
  
  <p>If anyone knows how to get this to work with Internet Explorer, I would really appreciate it, thanks!</p>