The cell of Tablelayout. The child component of Tablechildren only can be Panel.

<?xml version="1.0" encoding="UTF-8"?>

<?component name="panel" extends="panel" width="200px" height="200px" ?>

<zk>
<label value="3 columns, 1 colspan, 1 rowspan"/>

<tablelayout id="tbl" columns="3">
        <tablechildren id="tc1" colspan="2">        
            <panel title="table1" border="normal"             
                 maximizable="true" collapsible="true" >                
                     <panelchildren>Panel</panelchildren>                    
             </panel>            
        </tablechildren>        
        <tablechildren>        
            <panel title="table2" border="normal"            
                 maximizable="true" collapsible="true">                
                 <panelchildren>Panel</panelchildren>                
             </panel>            
        </tablechildren>        
</tablelayout>
</zk>