How to dynamicaly set format to timefield

Hi,

I have a panel and a timefield on it.

I tried to set format in beforerender callback of my Panel:

Code:

onPanelBeforeRender: function(component, eOpts) {
    ...
    var timefield = component.down("#time");
    Ext.apply(timefield, {format: "my dynamic format"});
},

But it changed only text input format but combobox listitem format still default (see timefield-format.png). These listitems should be formatted also.

Any suggestions?

How to dynamicaly set format to timefield