mr Niemelä,
you should check for Apache Jakarta Commons FileUpload project. As you are probably struggling with encoding too, please notice that you should have Filter for character endoding and then you should be aware of method String value = item.org.apache.commons.fileupload.FileItem(String charset);
Also pages should have following settings:
<%@page language="java" contentType="text/html;charSet=UTF-8" pageEncoding="UTF-8"%>
<head>
<META http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
also I think you might have to set response encoding..
response.setCharacterEncoding("UTF-8");
I hope this will help you..