Help me! i have a trouble using JSON in Perl

i had a error when i parsed JSON.
i am using module of the WebService::Simple to send request to Google Ajax Search API.

try below codes, for example.

#!/usr/bin/perl
use strict;
use warnings;
use utf8;
use WebService::Simple;
use WebService::Simple::Parser::JSON;
use Data::Dumper;

my $q = 'ケーキ www.bob-an.com/recipe/OutputMain.asp?KeyNo=15711';

my $parser = WebService::Simple::Parser::JSON->new;
$parser->{json}->utf8(1);

my $google = WebService::Simple->new(
    base_url        => 'http://ajax.googleapis.com/ajax/services/search/web',
    response_parser => $parser,
    params          => {
        q     => $q,
        v     => '1.0',
        rsz   => 'large',
        lr    => 'lang_ja',
    },
);

my $req = $google->get;
my $res = $req->parse_response;

print Dumper($res);

this is the error.

illegal backslash escape sequence in string, at character offset 383 (before "\\\x{30af}\x{30ea}\x{30b9}...") at /usr/lib/perl5/site_perl/5.8.6/WebService/Simple/Parser/JSON.pm line 27. 

illegal backslash escape sequence...

if the query changed, it is alright.

my $q = 'www.bob-an.com/recipe/OutputMain.asp?KeyNo=15711'; 

why? why? why?

it seems bad around '</b>' i guessed.
however i can not solve it.

please, help me.