.xls attachement saved as corrupt data

Question

My code to download and save attached files for an email works for attached text files, .xml files .csv files. but for attached .xls files, the resulting file is currupt - it opens in Excel but just displays strange characters. is there a different way to save this type of file?
Object o = message.getContent();
                            System.out.println("Content: "+o);
                            if (o instanceof MimeMultipart) { //attachements available?
                                MimeMultipart mm = (MimeMultipart) o;
                                int mmCount = mm.getCount();
                                for (int m = 0; m < mmCount; m++) { // for each part
                                    Part part = mm.getBodyPart(m);
                                    String disposition = part.getDisposition();
                                    if (part.getFileName() != null) {
                                        if ((disposition != null) && ((disposition.equals(Part.ATTACHMENT) || disposition.equals(Part.INLINE)))) {
                                            File tempFile = new File("D:\\TEMP\\mailtest\\" + part.getFileName());
                                            FileOutputStream fos = new FileOutputStream(tempFile);
                                            part.removeHeader("Content-Type");
                                            part.removeHeader("Content-Transfer-Encoding");
                                            part.removeHeader("Content-Disposition");
                                            part.writeTo(fos);
                                    } else { // part has no file name
                                        System.out.println("Part "+m+" has no file name!");
                                }//next part

Answer 1

the problem is to use part.writeTo(). if you use part.getInputStream(), it works:
if ((disposition != null) && ((disposition.equals(Part.ATTACHMENT) || disposition.equals(Part.INLINE)))) {
                                            InputStream is = null;
                                            File tempFile = new File("D:\\TEMP\\mailtest\\" + part.getFileName());
                                            FileOutputStream fos = null;
                                            try {
                                                fos = new FileOutputStream(tempFile);
                                                is = part.getInputStream();
                                                int byteCount = 0;
                                                byte[] bytes = new byte[128];
                                                while ((byteCount = is.read(bytes, 0, bytes.length)) > -1) { //use full read() method for GZIPInputStream to be treated correctly
                                                    fos.write(bytes, 0, byteCount);     
                                            } finally {
                                                try { if (fos != null) fos.close(); } catch (IOException ioe) {}
                                                try { if (is != null) is.close(); } catch (IOException ioe) {}