[GeoNetwork-users] high cpu usage (100%) in geonetwork 2.6.4 with tomcat 7, java 6/7 after a long time run

Hi,
In tomcat log, some warnings are logged:
The web application [/geonetwork] appears to have started a thread named
[Thread-2] but has failed to stop it. This is very likely to create a
memory leak.
...
validateJarFile(/var/www/website/geonetwork/web/geonetwork/WEB-INF/lib/servlet-api-2.5-6.1.14.jar)
- jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class:
javax/servlet/Servlet.class

The server is an ubuntu 12.04 amd64, geonetwork is configured as tomcat7
with openjdk7. After a long time uptime of the server (about 60days),
this server got a high cpu usage (about 100%), and restart tomcat could
solve this problem, but reboot the server could solved this problem. So
is there any ways to avoid to reboot the server?

Thanks.

Liangxu Wang