Normal Here is the zul to reproduce
<div> <listbox width="300px" checkmark="true" multiple="true"> <listhead> <listheader> <label value="Can an empty list be all selected?"/> </listheader> </listhead> </listbox> </div>
It looks like the due to the way _isAllSelected() implemented in SelectWidget
_isAllSelected: function () { for (var it = this.getBodyWidgetIterator({skipHidden:true}), w; (w = it.next());) if (!w.isDisabled() && !w.isSelected()) return false; return true; },
When nothing exist, this function returns true, hence the checkbox is checked.