Datefiled setvalue doesn't work on IE9

[leowll]

var rec = userInfoGrid.getSelectionModel().getSelected();
var crtDate = new Date(rec.get('crtDate'));
var updDate = new Date(rec.get('updDate'));
userInfoPanel.getForm().findField('crtDateField').setValue(crtDate.format('Y-m-d'));
userInfoPanel.getForm().findField('updDateField').setValue(updDate.format('Y-m-d'));

Here I met a problem. setValue works on google chrome but not on IE9, anyone have any solutions?

I use Extjs 3.4