Form_validation - checking checkboxes problem. Any help appreciated! (CI 1.7)

[eluser]crumpet[/eluser]
You need to use this command
$this->form_validation->set_message('rule', 'Error Message');

unfortunately it overrides all of the instances of that rule so if you used required elsewhere it will display the text you change it to.. try using isset for checkboxes (that is what the basis for the required rule is anyways) and then change the error message for isset to whatever you want.