The short answer is jars that are particular to a webapp can go in
WEB-INF/lib, however since database access is fairly common, your jdbc jars
and db specific driver jars should go above the webapp directory into
$TOMCAT_HOME/lib.
However, AFAIK some jars need to be in $TOMCAT_HOME/lib due to
Hello:
I'm using Tomcat 6.0.23
Yes, I know is an old release
Anyway, I would like to use tomcat-jdbc connection pool JAR
So, I 've stored a context.xml into META-INF folder in my WAR, as
Context
Resource auth=Container type=javax.sql.DataSource