Here is my problem.
What am i suppose to do if given this first drop menu:

<sql:query var="area">
SELECT NAME, COUNTRY, CODE FROM AREA ORDER BY NAME, COUNTRY
</sql:query>


<select name="from" size="1">
<c:forEach var="place" items="${area.rows}">
<option value="${place.code}">${place.name},
${place.country}</option>
</c:forEach>
</select>

the option are from database (let say table a) and this is the 2nd drop menu from table b,

<sql:query var="dest_area">
SELECT NAME, COUNTRY, CODE FROM AREA JOIN LENGTH ON AREA.CODE = LENGTH.DEST_CODE WHERE ORIG_CODE = '?problem?' ORDER BY NAME, COUNTRY
</sql:query>

<select name="to" size="1">
<c:forEach var="place" items="${dest_area.rows}">
<option value="${place.code}">${place.name},
${place.country}</option>
</c:forEach>
</select>

I want to filter the second menu from selected item from first menu.For example if user select 'a' from first menu then the second menu will list only 't' and 'r' on the 2nd menu..not list all value from database..what should i wrote at ?problem? in the sql query???need help plezzz.