This is untested and I have to rush off but I hope it works 
#!perl
use strict;
use warnings;

use LWP::UserAgent;
use HTTP::Headers;
use HTTP::Request;

my $content = join '', <DATA>;

my $ua = LWP::UserAgent->new();

my $h = HTTP::Headers->new(
    Content_Disposition => 'form-data; name="fname"; filename="deposit
+1.xml"',
    Content_Length      => length($content),
    Content_Type        => 'text/xml'
);

my $r = HTTP::Request->new('POST', 'http://search.cpan.org/', $h, $con
+tent);

my $response = $ua->request($r);

__DATA__
<?xml version="1.0"?>
...

[download]
   larryk                                          
perl -le "s,,reverse killer,e,y,rifle,lycra,,print"

In reply to Re: Setting Content-Type when POSTing with LWP by larryk
in thread Setting Content-Type when POSTing with LWP by koscher

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