[Deff]

<form id='form' action="1.php method=POST">
  <input id='fild_1' type='hidden' value=''>

  <input type=submit>
</form>
....
<a href="12345.html" onclick="Submit_href(this.href);return false">Ссылка</a>
<script type="text/javascript">
 function Submit_href(a) {
   var b=document.getElementById('form');
   b.document.getElementById('fild_1').value=a;
   b.submit();
   alert(a)
 }
</script>