This is known issue but it should be already fixed with latest GateIn version. The issue was that GateIn error page didn't return HTTP header "Content-type" and so that Apache is attaching Content-type header "text/plain" . And that's why you are seeing code. I think you can fix it by:
- update to latest GateIn trunk
- In your Apache httpd.conf change property DefaultType to "text/html" (default value is "text/plain" )
Hope this helps,
You don't need to use both options (Update trunk and Change Apache) but you can choose only one (Sorry for not making it clear from previous comment)
Thanks for the help.