jquery enable submit button

function disable(i){
    $("#rbutton_"+i).prop("disabled",true);
}

//jQuery 1.6+ use:
$("#submitButtonID").prop('disabled', true); //disable 
$("#submitButtonID").prop('disabled', false); //enable

//jQuery 1.5 and below use:
$("#submitButtonID").attr('disabled','disabled'); //disable 
$("#submitButtonID").removeAttr('disabled'); //enable