Zend_search_lucene and variables

[eluser]Unknown[/eluser]
I have integrated and loaded Zend/search library according to:
http://www.cmjackson.net/2009/02/17/how-...deigniter/

But when I try to assign the search instance to $this->siteindex I get very strange error.

Code:

$this->siteindex = new Zend_Search_Lucene('/path/to/site_index', true);

Gives me:

Warning: require(../../system/libraries/Exceptions.php) [function.require]: failed to open stream: No such file or directory in /var/elenia_apps/system/codeigniter/Common.php on line 127

Fatal error: require() [function.require]: Failed opening required '../../system/libraries/Exceptions.php' (include_path='.:/usr/share/php:/usr/share/pearystem/modules/lucene/libraries') in /var/elenia_apps/system/codeigniter/Common.php on line 127

What's happening here? I don't want to reload the index for each and every function.
This works fine:

Code:

$siteindex = new Zend_Search_Lucene('/path/to/site_index', true);

Thanks,
Andreas