how to use tablelayout in zk framework

I am new to ZK framework and i am using its latest version.I am trying to use tablelayout in zul but its giving error.tried importing zkmax.jar but it did not work for me.can somebody help? here is the sample code:

<tablelayout columns="2">
    <tablechildren>
        <panel title="Table 1" border="normal" maximizable="true"
            collapsible="true" width="200px" height="200px">
            <panelchildren>Panel Content</panelchildren>
        </panel>
    </tablechildren>
    <tablechildren>
        <panel title="Table 2" border="normal" maximizable="true"
            collapsible="true" width="200px" height="200px">
            <panelchildren>Panel Content</panelchildren>
        </panel>
    </tablechildren>
    <tablechildren>
        <panel title="Table 3" border="normal" maximizable="true"
            collapsible="true" width="200px" height="200px">
            <panelchildren>Panel Content</panelchildren>
        </panel>
    </tablechildren>
    <tablechildren>
        <panel title="Table 4" border="normal" maximizable="true"
            collapsible="true" width="200px" height="200px">
            <panelchildren>Panel Content</panelchildren>
        </panel>
    </tablechildren>
</tablelayout>
Error:

java.lang.ClassNotFoundException: org.zkoss.zul.impl.api.XulElement

Solution

that is true, i checked it later.but i found that suggestion in zk forum and so i tried.I have found the solution. I am actually using free edition and those components are available in PE & EE not in CE. :) For reference http://www.zkoss.org/whyzk/Features . Thanks Anyway..!!