Atmosphere's Module for Native Comet Support. Those modules are shared between Atmosphere 1.0.x and 2.0.x. With 1.0.x, they are rebundled with the same version of Atmosphere.
<dependency>
<groupId>org.atmosphere</groupId>
<artifactId>atmosphere-compat-{tomcat|tomcat7|jbossweb}</artifactId>
<version>2.0.0</version>
</dependency>Read this page for more information.