// Example:
//<a href="javascript:postlink('post.aspx',{user:'peter',cc:'aus'})">click</a>

function postlink (url,params) {
  var myForm = document.createElement("form");
  myForm.method="post" ;
  myForm.action = url ;
  for (var key in params) {
    var myInput = document.createElement("input") ;
    myInput.setAttribute("type", "hidden") ;
    myInput.setAttribute("name", key) ;
    myInput.setAttribute("value", params[key]);
    myForm.appendChild(myInput) ;
  }
  document.body.appendChild(myForm) ;
  myForm.submit() ;
  document.body.removeChild(myForm) ;
}