Export xml returned http 500 error

[zjdick]

Hello，all

I want to export my template，i selected host “Template_Linux” and all its items and triggers.,Press button “Preview” ,i can seed the list of elements to be exported.

But when i pressed button "export",the IE returned :"Http 500:Server internal error".

Also i couldn't import the xml files,wen i pressed button "import",the next page had no contents and no infos.

In the apache's error_log,there had this infos:

[Thu Jan 28 08:01:24 2010] [error] [client 10.1.50.46] PHP Warning:  require_once(include/classes/class.domdocument.php) [<a href='function.require-once'>function.require-once</a>]: failed to open stream: No such file or directory in /var/www/html/zabbix/include/config.inc.php on line 74, referer: http://10.1.50.42/zabbix/export.php
[Thu Jan 28 08:01:24 2010] [error] [client 10.1.50.46] PHP Fatal error:  require_once() [<a href='function.require'>function.require</a>]: Failed opening required 'include/classes/class.domdocument.php' (include_path='.:/usr/share/pear:/usr/share/php') in /var/www/html/zabbix/include/config.inc.php on line 74, referer: http://10.1.50.42/zabbix/export.php

But i can't find the file class.domdocument.php anywhere.

What's the problem?What can i do?

If anybody kown,please help me !

Thanks!

PS:I had install the php-xml,my zabbix server verssion : 1.8.

[zjdick]

just because i did't restart apache ......

Now，the export has succeeded，but the import still failed.
apache error message like this：
PHP Fatal error: Call to undefined method CTemplate::add() in /var/www/html/zabbix/include/export.inc.php on line 585,

[CeeEss]

Installing php-xml did not, at first, work under 3 pre-release versions of 1.8.1. After installing 1.8.1-release, export still failed. Restarting apache (which i had done during every installation of 1.8.1) cured the problem. Import now works, too. Hope it stays this way!