Video download in iPhone using jsp

I implemented video download using jsp.

It works fine in PC browsers and ANDROID.

It doesn't in 'iPhone'

Any one who knows why?? I'm still searching. Thanks.

<%@ page contentType="application/octet-stream;charset=utf-8" %>

<%@ page import="java.util.*" %>
<%@ page import="java.io.*" %>

<%
    out.clear();            // getOutputStream() has already been called for this response 예외를 처리하기 위한 구문
    pageContext.pushBody(); // getOutputStream() has already been called for     this response 예외를 처리하기 위한 구문

    InputStream     is  = null;
    OutputStream    os  = null;

    File            file    = new File( "/home/does/song", "Sc02.mp4" );        // 파일 불러올 때는 확장자도 일치해야 함. 혹은 소문자로.

    try {
        is = new FileInputStream( file );
    } catch( Exception e ) {
        out.print( e.getMessage() );
    }

    response.setContentType( "video/mp4" );
    response.setHeader("Content-Disposition", "attachment;filename=movie.MP4");
    response.setContentLength( (int)file.length() );
    response.setHeader("Pragma", "no-cache");


    os = response.getOutputStream();
    byte [] b = new byte[ (int)file.length() ];
    int leng = 0;

    while( ( leng = is.read(b)) > 0 )
        os.write( b, 0, leng );

    is.close();
    os.close();
%>