LWP Authorisation issue

[kapila]

I am trying to integrate Bugzilla with ReviewBoard writing code in perl. I have tried to write a code. curl command which is working

curl -k -H "Authorization: Basic YWRtaW4=" -X POST  -d "{\"repository_
+path\":":pserver:user:pwd@svn:/opt/cvsroot",\"username\":"admin",\"pa
+ssword\":"admin",\"submit-as\":"admin"}" "http://codereview.xyz.com/a
+pi/r/new/"

It is giving me full html page with js error

#!/usr/local/bin/perl

use LWP::UserAgent;
use MIME::Base64;

$url="http://codereview.xyz.com/api/review-requests/";
$newurl="http://codereview.xyz.com/r/new/";
$user="admin";
$pwd="admin";

$text="$user:$pwd";
$text = encode_base64($text);
#print "Encoded text: $text\n";
%param =(
        "repository_id" =>"cvsrepo",
        "repository_path" =>":pserver:user:pwd\@svn:/opt/cvsroot",
        "username" => "admin",
        "password" => "admin",
        "submit-as" => "username",
        );
   my $ua = LWP::UserAgent->new;
    $ua->timeout(TIMEOUT);
    $ua->protocols_allowed(['http', 'https']);
    $ua->default_header('Basic' => $text);
    $ua->credentials($newurl,$user,$pwd);

        $resp = $ua->get($url);
        print($resp->status_line(), "\n");

print("Add handler:\n");
        $ua->add_handler( response_header => sub { print "HANDLER\n"; 
+}, %param);
        print $ua->handlers('response_header', $resp)."\n";
push @{ $ua->requests_redirectable }, 'POST';
print $ua->show_progress."\n";
my $response = $ua->post($newurl,%param);

 if ($response->is_success) {
     print $response->decoded_content;
 }
 else {
     die $response->status_line;
 }

Error its not posting ..

 <h1>JavaScript is turned off</h1>
     <p>Review Board requires JavaScript in order to function.
     Please turn it on in your browser preferences.
     <p>Firefox users: if you prefer to turn on JavaScript only
     for specific sites, we recommend the
     <a href="https://addons.mozilla.org/en-US/firefox/addon/722">NoSc
+ript
     extension</a>.</p>