javax.servlet.ServletException
org.apache.catalina.security.SecurityUtil.execute
(SecurityUtil.java:294)

Solution:

Create 20servlets.policy:

nano -w /etc/tomcat5.5/policy.d/20servlets.policy

And add:

grant codeBase "file:${catalina.base}/webapps/-" {
permission java.security.AllPermission;
};

And restart Tomcat

/etc/init.d/tomcat5.5 restart