怪异问题，请大家帮助 SERVLET request.getInputStream 得不到值

代码如下：

import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import lotus.domino.*;


public class UploadServlet extends HttpServlet {
  Vector threadGroup=new Vector();
  int threadcount=0;
 
  public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException
  {
    
    String dbname=request.getParameter("dbname").trim();
     String docid=request.getParameter("docid").trim();
    String path="C:\\Embed\\";
    String file=null;
    String filename=null;
    String userIP=request.getRemoteAddr();
    String type=request.getContentType();
    String msg,temp$;
    FileOutputStream fileOut=null;
    boolean flag;
    boolean start=false;
    boolean filewrite=false;
    byte[] buf=new byte[1024];
    byte[] temp;
    int len,len2,len3,index;
    ServletInputStream in = request.getInputStream();
    try{
      File filepath=new File(path);
      if(!filepath.exists()){
          flag=filepath.mkdir();
      }
      int fi=type.indexOf("boundary=");
      String boundary=type.substring(fi+9);
      len=in.readLine(buf,0,buf.length);
      msg=new String(buf,0,len);
      len3=0;
      int nn=0;
      while(true){
          if((!start)&&(!filewrite)){
              index=msg.indexOf(boundary);
              if(index!=-1){
                 start=true;
              }
              len =in.readLine(buf, 0, buf.length);
              if(len==-1){
                  break;
              }
              msg=new String(buf,0,len);
          }
          if(filewrite){
              temp=new byte[1024];
              len2=in.readLine(temp,0,temp.length);
              msg=new String(temp,0,len2);
              index=msg.indexOf(boundary);
              if(index==-1){
                  len3+=len;
                  fileOut.write(buf,0,len);
              }else{
                  filewrite=false;
                  len3+=len-2;
                  fileOut.write(buf,0,len-2);
              }
              buf=new byte[1024];
              len=len2;
              for(int i=0;i<len;i++){
                  buf[i]=temp[i];
              }
          }
          if(start){
              index=msg.indexOf("name=");
              if(index!=-1){
                  start=false;
                  filewrite=true;
                  temp$=msg.substring(index+"name=\"".length());
                  file=temp$.substring(0,temp$.indexOf("\""));
                  file=file.substring(file.lastIndexOf("\\")+1);
                  filename=path+file;
                  fileOut=new FileOutputStream(filename);
                  len=in.readLine(buf,0,buf.length);
                  msg=new String(buf,0,len);
              }else{
                  break;
              }
          }
          nn+=1;
      }
      fileOut.close();
    }
    catch(IOException e){
      //System.out.println(e);
      //System.out.println(e.getMessage());
    }
    response.setStatus(response.SC_NO_CONTENT) ;
  }
  }
} --------------------编程问答-------------------- len=in.readLine(buf,0,buf.length);
这行读过来是空的 --------------------编程问答-------------------- len=in.readLine(buf,0,buf.length);
这个LEN为1024，
msg=new String(buf,0,len);
这个MSG的长度也是1024，但内容是空的

为什么啊？谁可以解决！
--------------------编程问答-------------------- 我的环境是在DOMINO下，在DOMINO r5.10 可以，一切正常，但在DOMINO r7 下同样的SERVLET程序就不好用了，

补充：Java ,  Web 开发