Custom 404 error page when managed server is up but the application is down

Dears,

We were trying to find a way to customize 404 error page received from Weblogic when managed server is up but the application is down. We've already added <error-page> to the application's web.xml, but of course that only works if the application is up.

So in our case, the application is down and managed server is up, when a user tries to access a page on the application, instead of receiving our custom 404 error page, he receives the Weblogic default 404 error page.

Is there a way to customize that default response of Weblogic?

Thanks,

Mohab.