I was on the verge of posting a question, but since I've figured it out, will post the answer for the next person who runs into this. When setting up Logback-access under Tomcat (as described here http://logback.qos.ch/access.html), if you make the mistake of putting the logback-access jar in your webapp's lib directory (in addition to putting in tomcat's lib directory as the directions specify), you will get this exception when you try to hit the servlet: java.lang.ClassCastException: ch.qos.logback.core.BasicStatusManager cannot be cast to ch.qos.logback.core.status.StatusManager Cheers, Eric