Apparently there is a provision[0] that makes EPL-licensed code, wich is the case of Arquimedes CAD by IME/USP fellows, compatible with GPLv3, thus compatible with LibreDWG without any weird linking arrangements.
[0] http://www.fsf.org/blogs/licensing/using-the-gpl-for-eclipse-plug-ins -- Rodrigo Rodrigues da Silva http://metamaquina.com.br http://garoa.net.br http://polignu.org http://gnu.org
