When developing web application with Eclipse (Helios) the tomcat output is being sent to the console. Ok, but the messages are being translated to my OS language.
In
Try adding -Duser.language=en
in the bottom of your eclipse.ini which is found in your eclipse installation directory (keep a backup copy of the eclipse.ini before any changes).
Have you tried setting the following -D parameters in the launch configuration?
-Duser.language=en -Duser.country=US -Duser.variant=EN
Go to Window > Preferences > Java > Installed JREs > select preferred JRE > Edit and then add the following to Default VM arguments:
-Duser.language=en -Duser.country=US