geekgrrl and nmcfarl are correct about Javascript, but your tick() usage is wrong. You need to pass the value as the second arg: 

$agent->tick($chk_visa,'Visa');

[download]
Here are two test scripts for you, the first is a CGI script and the second is a W::M bot that queries the CGI script and tests its "return" value.

CGI script: 
use CGI::Pretty qw(:standard);

if (param('chklstCC:0')) {
   print header, param('chklstCC:0');
}
else {
   print header,start_html,start_form,
      checkbox_group(
         -name=>'chklstCC:0',
         -values=>[qw(Visa MasterCard Discover)],
      ),
      submit('go'), end_form, end_html,
   ;
}

[download]
Bot script: 
use WWW::Mechanize;
use Test::More qw(no_plan);

my $bot = WWW::Mechanize->new();
$bot->get('http://localhost/path/to/cgi_script.cgi');

$bot->tick('chklstCC:0','Visa');
$bot->submit;

is( $bot->content(), 'Visa', "Got expected content" );

[download]

UPDATE: (a reply)
No value? Then those aren't "real" checkboxes, are they? Value is a required attribute for the checkbox input type. I gave you correct usage for correct HTML. The checkboxes you are trying to check rely on Javascript, and you will too if you want this bot to work. I have used Javascript with success before, code is at (jeffa) Re: Encrypt web files!. Good luck, you're gonna need it. :/

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: Clicking a checkbox using www::mechanize by jeffa
in thread Clicking a checkbox using www::mechanize by Anonymous Monk

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