Thread:Extension talk:Pdf Export/Cannot install extonsion on mediawiki 1.21 (2)

Hi all, when I downloaded and install this extension, I cannot run my wiki because of HTTP 500 internal error. When I removed it (#in LocalSettings.php) it works again. I tried with htmldoc and with DomPdf, and nothing. I'm running on Centos 6.4 and I have installed theese extensions: ApprovedRevs, FlaggedRevs

Do you have some idea where should be problem? Thank you

Ivo