<?php
  $page['content']['system_main']['name']['#title'] = '用<em></em>户<em></em>名';
  $page['content']['system_main']['name']['#description'] = '请输入用户名';
  $page['content']['system_main']['pass']['#title'] = '密<em></em><em></em>码';
  $page['content']['system_main']['pass']['#description'] = '密码由6-16位数字或字母组成，字母区分大小';

  //captcha
  //$page['content']['system_main']['captcha']['#description'] = '看不清，点击图片换一张';
  unset($page['content']['system_main']['captcha']['#description']);
  $page['content']['system_main']['captcha']['captcha_widgets']['captcha_response']['#title'] = '验<em></em>证<em></em>码';
  $page['content']['system_main']['captcha']['captcha_widgets']['captcha_response']['#description'] = '看不清，点击图片换一张';

  $page['content']['system_main']['actions']['submit']['#value'] = '登陆';

  $csna = $page['content']['system_main']['submitted'];

  unset($page['content']['system_main']['submitted']);

  $qq_login = $base_url . '/' . path_to_theme() . '/images/qq_login.png';
  $sina_login = $base_url . '/' . path_to_theme() . '/images/sina_login.png';

  $csna['user_login_block']['#suffix'] = '<h1>使用其他账号登陆</h1><div class="item-list"><ul class="csna-items"> <li id="csna_provider_weibo" class="last"><a href="/csna/weibo"><img typeof="foaf:Image" src="' . $sina_login . '" alt="新浪微博登陆" title="新浪微博登陆" /><span>新浪微博登陆</span></a></li><li id="csna_provider_qq" class="first"><a href="/csna/qq"><img typeof="foaf:Image" src="' . $qq_login . '" alt="腾讯微博登陆" title="腾讯微博登陆" /><span>腾讯微博登陆</span></a></li> </ul></div>';
?>

提示 $csna = $page['content']['system_main']['submitted'];  这行