mailbody=(MimeMultipart)mail.getContent();
......
java.io.FileInputStream fin= new java.io.FileInputStream(filename);
javax.activation.DataSource source = new MyByteArrayDataSource(fin,
FileTypeMap.getDefaultFileTypeMap().getContentType(upfile));
MimeBodyPart attachbp=new MimeBodyPart();
attachbp.setDataHandler(new javax.activation.DataHandler(source));
// attachbp.setFileName(upfile);
attachbp.setFileName("=?GB2312?B?"+Com.tbr.util.Base64.encode(upfile.getBytes())+"?=");
mailbody.addBodyPart(attachbp);
mail.saveChanges();
....
