title: Jquery ajax.post() ie security issue
body: <p>i got simple jQuery ajax post request</p>
  
  <pre><code>$.ajax({
      url: "/_layouts/TK_Editor/DemoHandler.ashx",    //
      contentType: "application/json; charset=utf-8", //cherset set
      type: 'POST',                                   //
      dataType: "json",                               //
      data: JSON.stringify(json_str),                 //
      success: OnComplete,                            //function
      error: OnFail                                   //function
  });
  </code></pre>
  
  <p>I browsed dozens of similar problemms here and google, but most of them are about crossdomain or character set, well i got no crossdomain, no anything complicated. 
  works just fine in ffox, chrome, even opera...
  after json_str parsed by DemoHandler, web service execs some TSQL procedures, but when i try to make ajax request from IE (8+), my service doesn't exec any procedures and i got endless waiting till request fires.
  However, when i disable most all of security in IE, it suddenly works!
  Can anyone explain me why this happens and what exact option in security doesn't allow jQuery.ajax request to fire well, and if it is possible - how to avoid this scenario?</p>
  
  <p>p.s: webservice works just fine too, described in <a href="https://stackoverflow.com/questions/12401239/pass-jquery-json-into-asp-net-httphandler" title="json parsing with asp.net webservice">here</a></p>