I need HELP retrieving a parameter

I'm sending some input from a form to a servlet.
Now, I can retrieve the correct values of all fields in the form, that is, all except one. The "nasty" field is a list with multiple selection enabled and problem is that I get only the first selected value from the list.
I would greatly apreciate ANY idea as to how can I retrieve ALL selected values from the list. BTW I also have no clue as how the selected values are separated in the string received from the getParameter method.
Thanks for your concern!
Peter.