I'm using Perl's LWP and HTTP::Request::Common modules to POST a multipart/form-data form to upload a file to an Apache 1.3.6/PHP 3.0.12 web server.

The problem comes when PHP goes to MIME unencode the POST.  mime.c's php3_mime_split function looks for one of four things to be in the POST:  the boundary, the Content-Disposition header, a plain form-data field, or the uploaded file field (with a Content-Type header).  But Perl's HTTP::Request::Common puts in an additional header: Content-Length.

According to the RFC (RFC 1867), this seems legal.  So when Perl sends:

Content-type: multipart/form-data, boundary=AaB03x
--AaB03x
Content-Disposition: form-data; name="field1"

Joe Perl
--AaB03x
Content-Disposition: form-data; name="uploadfile"; filename="file1.txt"
Content-Length: 5660
Content-Type: text/plain

         ... contents of file1.txt ...
--AaB03x--


php3_mime_split saves the $uploadfile starting with "ntent-type: text/plain..." rather than the correct spot, which would be after the single \n by itself.