Have the JSP talk to a front controller servlet. When you make a selection in the first list box, submit the form to the servlet. Let the servlet put the contents of the second list box into request scope as a list of strings and forward the response back to the original JSP.
You should be using JSTL to keep scriptlet code out of your JSPs, of course.
%
U can do that using javascript function....
For example , try the following code ::::::
*************************************************************
<script language="javascript">
function fnAssignValue() {
document.myForm.select2.value = document.myForm.select1.value ;
}
</script>
<form name="myForm" >
<select name="select1" onChange="javascript:fnAssignValue();">
<option value="0">0</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
<select name="select2" >
<option value="0">no value</option>
</select>
</form>
*************************************************************
Thanks,
Anurag