Latest versions of Apache/Tomcat for BO65SP3

What are the latest versions of Apache/Tomcat that can be used with Business Objects 6.5 sp3 i.e. are particular Apache/Tomcat versions bundled with a Business Objects release

We have had doubts cast over the security features of the versions of Apaceh/Tomcat we use and need to know whether we can use later versions of Apache/Tomcat, whilst retaining existing version of Business Objects 6.5.3 ?