This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
Your application server should have a log file. The appliation servers I've worked with the name is configurable. On Sun servers its called server.log. Also, since it looks like the problem is happening in your filters you might want to post your web.xml.