Pre-populated option values of a select not got on Submit

[Sridhar Raman]

I have a select/option in my JSP like this:
<html:select size="3" styleClass="menu" styleId="catsel" property="category"
multiple="yes">
   <html:options collection="catSelList" labelProperty="displayName"
property="id"/>
</html:select>

I have also defined the bean for catSelList:
<bean:define id='catSelList' property='catSelList' name='editEPForm'/>

In the Form java file, I have the method public Collection getCatSelList(),
that returns the list of values that needs to be displayed in the
select/option menu.

The page works fine when opened. The values that need to be displayed in the
options are displayed correctly. But the problem occurs on submit.

Whatever I do, the property category (which refers to the html:select) is
always null. Even if I add values from another list into this select/option
menu, the value of category on submit is null. How do I rectify this
problem?

This is what I want - if the user doesn't change anything in that field, the
pre-populated values needs to be stored under category. If he does change
anything, the new values needs to be stored under category.

How do I do this?

Thanks,
Sridhar