How is the Java classpath set on a Mac?
On Mac OS X, I stopped using the CLASSPATH environment variable some time ago; I now set it for each project. Too often, I would forget about older, conflicting JARs hiding in the forgotten recesses of an ever growing list of paths. In particular, I don't know of a reason to set it for Tomcat. If you're curious, $CATALINA_HOME/bin/setclasspath.sh may be informative.
If you need it for some other reason, the bash incantation to include this or that is shown below:
export CLASSPATH=.:/opt/this/this.jar:/opt/that/that.jar:…