I've added a <filter> and a <filter-mapping> to web.xml that turns a functioning Tomcat 6.0 system into one with severe startup errors in catalina.log. My first thought is that the errors are caused by the new filter using the same filter-class as an existing filter (since the other additions are just params). Are two filters with the same filter-class permissible in Tomcat?
The filter class that's used twice handles single-sign-on. All the current pages are behind SSO. I've added a JSP page that requests user input before redirecting to the app's normal startup page, and it needs to be behind SSO as well. The two filters are necessary (as far as I know) because the url-patterns are different.
Here's the portion of catalina.log that's generated when Tomcat starts: