$(document).ready(function(){   
 $("#hgnlunsubscribe").click(function(event){
   mail = $("#hg_input_nl_address")[0].value;
   if(mail){
     $("#hg_input_nl_unsubscribe")[0].value=mail;   
     document.HG_Newsletter_Unsubscribe.submit(); 
   }   
   event.preventDefault();
 });
});