translate(localize) specific title of web form use preprocess func
The code doesn't work because the function receives only a parameter, and that is not $node. The correct code should eventually be the following one.

function mymodule_preprocess_page(&amp;$variables) {  
  if(!empty($variables['node']) &amp;&amp; $variables['node']-&gt;nid == 6) {
    $variables['title'] = t($variables['title']); 
  }
}


I am assuming you want to change the title when the node ID is equal to 6.