on that page you could have a hidden field called "all_checkboxes" or something. using various javascript and DOM stuff, you can get the values of the checkboxes (note: JS code below is just pseudo-code). on the onSubmit event, populate that field with something like... 
for(var i=0; i<total_checkboxes; i++) {
   if(checkbox = 'checked') {
      all_checkboxes.value += userid + '|||';
   }
}

[download]
before the submit occours, that field should look something like "2|||3|||8|||20|||". Only filled with the checked userids.

then in your cgi script, split that field using a split command... 
my @userids = split('|||', $cgi->param('all_checkboxes');

[download]

In reply to Re: OT? Checkbox list with CGI/Javascript by ickyb0d
in thread OT? Checkbox list with CGI/Javascript by rashley

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