CMS变得简单，包括文件在内的麻烦

我在用户定义的标签中使用 php include（） 时遇到了一点问题。就像在CMSMS手册中描述的那样，您可以通过用户定义的标签将PHP代码添加到CMSM页面中。我努力了，但它不起作用。这是我只想添加的代码：

<?php
    $site="true";
    include("/home/www/web23/html/wbt/index.php");
?>

我收到此错误：

Warning: include(wp.php) [function.include]: failed to open stream:
   No such file or directory in 
    C:'xampp'htdocs'cmsms'lib'classes'class.usertagoperations.inc.php(260) :
     eval()'d code on line 1 
Warning: include() [function.include]: Failed opening 'wp.php' for inclusion 
   (include_path='.;C:'xampp'php'PEAR')
     in C:'xampp'htdocs'cmsms'lib'classes'class.usertagoperations.inc.php(260) :
      eval()'d code on line 1