title: Dokeos warning: Strict Standards
body: <p>When installing dokeos 2.1 into htdocs, it shows warnings like these:</p>
  
  <pre><code>Strict Standards: Declaration of SortableTableFromArray::get_table_data() should be compatible with that of SortableTable::get_table_data() in ...\dokeos\main\inc\lib\sortabletable.class.php on line 989
  
  Strict Standards: Declaration of SortableTableFromArrayConfig::get_table_data() should be compatible with that of SortableTable::get_table_data() in ...\dokeos\main\inc\lib\sortabletable.class.php on line 1032
  </code></pre>
  
  <p>and about ten same warnings like this:</p>
  
  <pre><code>Strict Standards: Only variables should be passed by reference in ...\dokeos\main\inc\lib\internationalization.lib.php on line 203
  </code></pre>
  
  <p>How to solve this?</p>