/usr/share/tomcat6/lib/jasper-jdt.jar is in tomcat6-common 6.0.35-1ubuntu3.11.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/tomcat6/lib/../../java/ecj.jar
/usr/share/tomcat6/lib/../../java/ecj.jar