Honestly, the browser's back button and dynamic web applications do not play together very well. If you explain in more detail what you are trying to do, maybe somebody can offer some tips.
I have a page that displays the information about the current page so when i go to the information page there is a back button so when I click it i return to the first jsp but my drop downs get reseted...
Anil, What is remembered using the back button in the browser depends on the browser's settings.
If you are talking about a "back to link" in your app, you have more control since you get to repaint the page. In this case, make sure your form values are still set and that the form is in your session. Then repaint the page.