[TYPO3-english] Server error 500

[Karin Meulengrath]

Hi list

I have just upgraded to 4.5.2. After the upgrade, I get a problem. I cann't 
edit pages in the backend. Once I hit 'edit' I get a server 500 error.

Also I have an error showing up in my report:

"PHP Doc CommentsStrippedThe PHP Doc comments are stripped from the PHP 
files. All extensions based on Extbase will not work correctly.
Are you using a PHP Accelerator like eAccelerator? If you use eAccelerator, 
please recompile it with the compile 
flag --with-eaccelerator-doc-comment-inclusion. See the eAccelerator 
bugtracker for more details."

How can I solve this?

ThanksKarin