Upgrading to Java 1.5

[Jonathan Mast]

I'm working in a Java 1.4.2, Apache 1.3.33, Tomcat 5.5, Linux environment.
I want to migrate to Java 1.5.  Is it possible to do this vis-a-vis Tomcat
by just altering what the /usr/local/java link points to?  Or will I need to
do more under-the-hood changes?