If you ever wondered what happened with your special characters when filtering/searching, or if you are watching any of the following jira tickets:
OC-488, OC-489, OC-490, OC-503, OC-1429, OC-1527, OC-1529, OC-1530, OC-1531, OC-1532, OC-1533, OC-1534, OC-1597, OC-1654, OC-2133, OC-2351, OC-5699, OC-6911 (and I probably missed some)
then edit your server.xml to tell tomcat it must use utf-8 for the uri-encoding.
is described how.
Documentation can be found on https://wiki.apache.org/tomcat/FAQ/CharacterEncoding
and scroll to "What can you recommend to just make everything work? (How to use UTF-8 everywhere)."