BUG 8812 js error on Pausing case,its calendar shows error using IE SOLVED

- There's a JavaScript error when we want to pause a case on Internet Explore ver. 8 and 9.
- fixed issue with error on the calendar show for IE

workflow/engine/templates/cases/open.js

@@ -610,7 +610,8 @@ Ext.onReady(function(){
           fieldLabel: 'Unpause Date',
           name: 'unpauseDate',
           allowBlank: false,
-          minValue: new Date(filterDate)
+          value: filterDate,
+          minValue: filterDate
         })
       ],
       buttons : [