In order to use a custom jar Solr library, please send it to support@opensolr.com and our tech dept. will install it in your environment (you'll also need to specify your Opensolr Registration Email Address and the Opensolr Index Name), within about 24 hours (usually just takes a couple of hours if the plugin is fully compatible with your Solr version).

Make sure you send the .jar it's self, or links to official plugin page, where jar binaries are already compiled.