500 Internal Server Error when opening HTML e-mails [Roundcube]

I have ISPConfig 2.2.25 and using the latest version of RoundCube, v0.2-alpha. When opening HTML e-mails, I get a 500 Internal Server Error though nothing in error_log or access_log that is pertinent. I am using Debian Lenny. Any ideas?

Regards,

Lewis

 

Did you check the error log in /root/ispconfig/httpd/logs?

 

I did indeed. Nothing at all useful/relevant. Searching google shows several other people with the same problem (since upgrading to the latest version of RoundCube), but no resolution...

 

RoundCube has also it's own logs directory. Do you see any related errors in there?

 

Oooh - what do you make of the following:

[15-Sep-2008 13:00:09] PHP Warning: include_once(DOMDocument.php) [<a href='function.include-once'>function.include-once</a>]: failed to open stream: No such file or directory in /home/admispconfig/ispconfig/web/roundcubemail/program/include/iniset.php on line 76
[15-Sep-2008 13:00:09] PHP Warning: include_once() [<a href='function.include'>function.include</a>]: Failed opening 'DOMDocument.php' for inclusion (include_path='/home/admispconfig/ispconfig/web/roundcubemail/:/home/admispconfig/ispconfig/web/roundcubemail/program:/home/admispconfig/ispconfig/web/roundcubemail/program/lib:/home/admispconfig/ispconfig/web/roundcubemail/program/include:.:') in /home/admispconfig/ispconfig/web/roundcubemail/program/include/iniset.php on line 76
[15-Sep-2008 13:00:09] PHP Fatal error: Class 'DOMDocument' not found in /home/admispconfig/ispconfig/web/roundcubemail/program/lib/washtml.php on line 188

 

What's the output of

Code:

updatedb
locate DOMDocument.php

?

 

That file doesn't exist. What should I do?

 

Not sure - I've never tried the Roundcube package...