<hgroup>
  <button caption="prev" onclick="zenPage.prevTab();"/>
  <button caption="next" onclick="zenPage.nextTab();"/>
</hgroup>
<tabGroup id="tabGroup" showTabBar="true" onshowTab="zenThis.refreshContents();">
  <tab caption="tab1">
    <dynaGrid gridLabel="dynaGrid1">
      <gridColumn label="Col 1"/>
      <gridRow label="Row 1" />
    </dynaGrid>	
  </tab>
  <tab caption="tab2">
    <dynaGrid gridLabel="dynaGrid2">
      <gridColumn label="Col 2"/>
      <gridRow label="Row 2" />
    </dynaGrid>	
  </tab>
  <tab caption="tab3">
    <dynaGrid gridLabel="dynaGrid3">
      <gridColumn label="Col 3"/>
      <gridRow label="Row 3" />
    </dynaGrid>	
  </tab>
</tabGroup>

...

Method nextTab() [ Language = javascript ]
{
  var tab = this.getComponentById('tabGroup');
  tab.showNextTab();
}

Method prevTab() [ Language = javascript ]
{
  var tab = this.getComponentById('tabGroup');
  tab.showPreviousTab();
}