Default listitem renderers behave strangely in zk3.5.2

<zk>
	<zscript><![CDATA[

SimpleListModel levels = new SimpleListModel( new String[]{  "LOW", "MIDDLE", "HIGH" } );
]]></zscript>
	<listbox id="list" width="200px" rows="10" model="${levels}" />
<zscript>
<![CDATA[
for( li: list.getItems() ) {
    alert( "" + li.getValue() );
}
]]>
</zscript>
</zk>

<zk>
	<zscript><![CDATA[

SimpleListModel levels = new SimpleListModel( new String[]{  "LOW", "MIDDLE", "HIGH" } );
]]></zscript>
	<listbox id="list" width="200px" rows="10" model="${levels}" />
<button label="klikk!" onClick='showItems()' />
<zscript>
<![CDATA[
void showItems() {
for( li: list.getItems() ) {
    alert( "" + li.getValue() );
}
}
]]>
</zscript>
</zk>