Grid/listbox/tree don't support scrollTop well

It failed:

<window title="Live Data Demo" border="normal">
<zscript>
String[] data = new String[30];
for(int j=0; j &lt; data.length; ++j) {
data[j] = "option "+j;
}
ListModel strset = new SimpleListModel(data);
</zscript>
<listbox id="list" width="200px" rows="10" model="&#36;{strset}">
<listhead>
<listheader label="Load on Demend" sort="auto"/>
</listhead>
</listbox>
<button label="scroll" onClick='list.smartUpdate("scrollTop", "1000")'/>
</window>