Open EJB
A modular, configurable, and extendable EJB Container System that comes with Servers for both Local and Remote access comes with Servers for both Local and Remote access
Geronimo
Apache Geronimo is a new effort coordinated by the Apache Software Foundation to make a J2EE compatible container. Software Foundation to make a J2EE compatible container.
JBoss
JBoss is advanced middleware with a full J2EE based personality that IT departments look for. But that is not all, the OEM and ISV that IT departments look for. But that is not all, the OEM and ISV community embraced JBoss as a highly flexible service oriented architecture on which to build their own products.
JFox
JFox is an Open Source, standards-compliant, J2EE based application server implemented in 100% Pure Java, It comes from China application server implemented in 100% Pure Java, It comes from China Enterprise Open Source Community.
JOnOS
JOnAS is a full J2EE platform, developed within the ObjectWeb consortium (www.objectweb.org), currently in the process of passing the consortium (www.objectweb.org), currently in the process of passing the Sun J2EE 1.4 Certification.
Resin
Resin Open Source provides JSP, Servlet, and EJB functionality
EasyBeans
EasyBeans is an open-source lightweight EJB3 container implementation developed within the ObjectWeb consortium implementation developed within the ObjectWeb consortium (www.objectweb.org). It can be integrated within JOnAS and Tomcat