Question about linking the jsp input fields to the actionForm

Hi - I am a newbie to JSP and Struts
We have a jsp form for employees to change their contact information.
The fields are layed out so that it will have the "current information" and the "change to" information
ex.
                    Current Info            Change To
   Last Name   _____________     ________________

the current information is display only

Here's the question - when I create my actionForm do I need to have properties for both of these fields (i.e. a property for "currentLastName" and for "newLastName" or is there a way to use the same property for both of these fields?  I would want the "change to" fields to be blank unless the user inputs a value into the text box

thanks
Jen