JARs can be stored in three different locations in the lib directory, each
with a different purpose.
JARs in the development directory are only visible during compile time. Most
of these JARs are already included by the application server or are only useful
for a specific database (i.e., JDBC drivers).
JARs in the global directory are automatically copied to the application
server's global classpath and are visible by all applications loaded by the
application server.
JARs in the portal directory are automatically copied to the portal classpath
and are only visible by the portal.