problem with forceId

[Yaron Spektor]

Hi,
Does anyone know how to use the force id in a component?
I looked for an answer but could not see this even mentioned anywhere...

For example I use this tag:
                <t:inputCalendar id="cal1"  
                renderAsPopup="true"                
                popupDateFormat="MM/dd/yyyy" 
                helpText="MM/DD/YYYY"
                renderPopupButtonAsImage ="true"
                onchange="setDateString('cal1','cal2')"
forceId="true"
                size="7"
                />  

And I need id 'cal1' to be forced to true.
When I try and do it with HtmlInputCalendar components I don't have that
option.   

HtmlInputCalendar inputCalendar = new HtmlInputCalendar();
  String fullSrcId=idPrefix+"_"+id;  
  inputCalendar.setId(fullSrcId);
  inputCalendar.setRenderAsPopup(true);
  inputCalendar.setRenderPopupButtonAsImage(true);
  inputCalendar.setSize(7);
  inputCalendar.setPopupDateFormat("MM/dd/yyyy" );
//FORCE ID???????

Yaron