A couple of general notes in case you encounter problems.
It is important that the only jndi.jar, naming.jar and jdbc.jar's and
your jdbc driver are in the %CATALINA_HOME%/common/libs and/or %CATALINA_HOME%/libs folders.
If slide loads any of the classes from its own classloder it will either
not find the tomcat datasource or it will fail to load the DB drivers.
With Tomcat 4.0.1 the standard implementation provides a datasource which
has pooling. It has no configured limits, it will grow as required and lazily
shrinks to reduce its size. Tomcat also has the capability to support
other datasource implementations and will offer one based on the
Apache commons DBCP pool implementation in version 4.1.