multipart problem

I have a apache+php server which returns multipart message.

Here is the php code generating the message:
<?php
header("x-up-mmsapi-version: 1.00");
header("Content-Type: multipart/related;boundary=PDC;type=text/plain");
echo "\n\n--PDC\n";
echo "Content-Type: text/plain\n\n";
echo "TRANID: 0000002962 COMMAND_ACK:1000 COMMAND ACKNOWLEDGED\n";
echo "--PDC--\n";
?>

This is how the message looks like.
HTTP/1.1 200 OK
Date: Fri, 23 Aug 2002 06:40:39 GMT
Server: Apache/1.3.26 (Unix) PHP/4.2.2
X-Powered-By: PHP/4.2.2
x-up-mmsapi-version: 1.00
Keep-Alive: timeout=15,max=100
Connection: Keep-Alive
Transfer-Encoding: chunked
Content-Type: multipart/related;boundary=PDC;type=text/plain

--PDC
Content-Type: text/plain


TRANID: 0000003029.COMMAND_ACK:4001 NO SUBSCRIBERS FOUND
--PDC--

When I use IE browser to access the URL, the bowser will prompt to ask if I
want to save the file (i.e. the message body).  However, I got "UNKNOWN
boundary!" error and fail get the message body using libwww.  Can anyone one
help? Thanks!

ChunkStream. Chunk 9e100 created with max size 0
Reader...... Created reader stream a34c8
Socket...... TCP send buffer size is 32768 for socket 4
Buffer...... Flushing a1398
Write Socket 317 bytes written to 4
Read Socket. WOULD BLOCK fd 4
Buffer...... Flushing a1398
Write Socket 8 bytes written to 4
Read Socket. 406 bytes read from socket 4
MIME header. Date: Fri, 23 Aug 2002 06:47:10 GMT
MIME header. Server: Apache/1.3.26 (Unix) PHP/4.2.2
MIME header. X-Powered-By: PHP/4.2.2
MIME header. x-up-mmsapi-version: 1.00
MIME header. Keep-Alive: timeout=15, max=100
MIMEParser.. Timeout after 15 secs
MIMEParser.. Max 100 requests pr connection
MIME header. Connection: Keep-Alive
MIMEParser.. HTTP/1.0 Keep Alive ignored
MIME header. Transfer-Encoding: chunked
MIME header. Content-Type: multipart/related;boundary=PDC;type=text/plain
Building.... C-T stack from multipart/related to */*
Boundary.... UNKNOWN boundary!
Building.... Content-Decoding stack
Building.... Transfer-Decoding stack
Chunked..... Decoder stream created
Chunked..... `63 ' chunk size: 63
Read Socket. Target ERROR -1
Chunkstream. FREEING...
Socket read. FREEING....
Socket write FREEING....

Regards
-----------------------------------------------------------------------
Lincoln Tang
Openwave Systems Inc.