Are your menu items just hyperlinks? You could ways invoke the struts action directly passing the task item in the URL directly. For example, if the action you are try invoke is called process.do and your menu item has three items you could render the urls for the items:
what you can do is to give seperate action path elements to each item in the side menu, and all this action path will refer to the same action class. In order to differentiate between each side item use the "parameter" attribute of the action element.
"Failure is not when you fall down; its only when you fail to get up again."