My scenario is the following:
I have a WebApp.war that is deployed to a servlet container. This WebApp.war contains in WEB-INF/lib the following libraries:
Since you are using Tomcat, you could leverage the VirtualWebappLoader.
Add a META-INF/context.xml whith
<?xml version="1.0" encoding="UTF-8"?>
<Context path="/somepath/myapp">
<Loader className="org.apache.catalina.loader.VirtualWebappLoader"
virtualClasspath="/somedir/*.jar"/>
</Context>
Remember also that the virtualClasspath attribute must be a absolute path, as correctly stated in the comment below.