The system locally caches dynamically-loaded JAR files. You should be aware that the date and time of the cached files are compared with the date and time of the library files whenever a new connection is created; the JAR files in the cache are refreshed if they are found to be out of date. This could mean that processing continues with a newer version of a JAR file after a connection has been created.

Note also that problems may arise if a custom security manager has been implemented, because the connection to the database will be refused.