javax.servlet.ServletException- Unable to validate ProxyTicketValidator

This problem may be due to following possibilities:

1. have u configured SSL?

2. Have u created keystore using "keytool" ?

3. The SSL certificate CN created using "keytool" is not matching the hostname from which request comes. DNS matters !!..

4. For java web application, the self signed certificate must go into jre directory.

5. Obvious situation, have u restarted tomcat after doing all these?.. 

Here are some steps to avoid this error: ( I did this for a simple java web app) 

$ keytool -genkey -alias tomcat -keyalg RSA

$ keytool -export -alias tomcat > /tmp/cert

as root,

# keytool -import -trustcacerts -alias tomcat -file /tmp/cert -keystore /ohome/jdk1.5.0_07/jre/lib/security/cacerts