title: HTML changes with element.setAttribute("onclick","alert('Test');") and element.onclick = "alert('Test');";
body: <p>I got surprised when comparing the following cases:</p>
  
  <pre><code>button = document.getElementById("addSugerenciaButton");
  
  if (button != null) {
     button.onclick = "post_to_url('" + addSugerenciaURL + "', idBuzon', '" + id + "');";
  }
  
  button = document.getElementById("removeBuzonButton");
  
  if (button != null) {
      button.onclick = function() {
          if (!confirm(removeSugerenciaMessage)) {
              return false; 
          };
          post_to_url(removeBuzonURL, 'idBuzon', id);
      };
  }
  
  button = document.getElementById("editBuzonButton");
  
  if (button != null) {
      button.setAttribute("onclick","post_to_url('" + editBuzonURL + "', 'idBuzon', '" + id + "');");
  }
  </code></pre>
  
  <p>Just the latter appeared to change the HTML (at least inspecting with Firebug) whilst the rest, although working properly too, they didn't show any onclick event in the editBuzonButton element.</p>
  
  <p>Any ideas why this is happening?</p>