Yesterday I fight with same problem. Problem for me was that nothing was mapped to /j_security_check (
servlet or page). I had only mapping with some servlets like '*.html', '*.jsp', '*.js', ... but none match /j_security_check. Because of this tomcat 7 decide not to start even filters which should be started '/*' (filter mapping isn't enough for tomcat 7). I add following line to web.xml and everything start to work: