<form action="/" accept-charset="UTF-8" method="post" id="search-block-form">    
<label for="search_theme_form">Custom Search</label>
<input type="text" name="search_theme_form" id="edit-search-theme-form-l" size="25" value="" title="Enter the terms you wish to search for." class="form-text" />
<input type="submit" name="op" value="GO!"  />
<input type="hidden" name="form_id" id="edit-search-theme-form" value="search_theme_form" />
<input type="hidden" name="form_token" id="a-unique-id" value="<?php print drupal_get_token('search_theme_form'); ?>" />
</form>