Hi Marco,
Can you give us your catalina.out log and the labkey.log file as well?
Your log files have a whole bunch of information that will be helpful in troubleshooting this problem vs the two lines you copy/pasted here.
Also, please provide us with a copy of your labkey.xml file under your CATALINA_HOME/conf/Catalina/localhost directory (Note: Please make sure to remove your credentials and database URL from the file).
And I would recommend you go back through our installation document and reconfirm everything you did:
https://www.labkey.org/Documentation/wiki-page.view?name=manualInstall
The reason why is that there are a lot of steps to install LabKey and missing a single step can create problems like this. I'm reasonably confident that if you recheck your installation steps against your actual server configuration, you will likely figure out what went wrong and make your necessary corrections.
Regards,
Jon