Ops, I missed it. It's here now:
6 - Add this to the web.xml
<description>Deployment Descriptor for BIRT Viewer. Please check and specify the following settings.</description>
<context-param>
<description>Flag whether the report resources can only be accessed under the working folder. Defaults to false</description>
<param-name>WORKING_FOLDER_ACCESS_ONLY</param-name>
<param-value>false</param-value>
</context-param>
<context-param>
<description>Temporary document files directory. Defaults to ${Context Root}/documents</description>
<param-name>BIRT_VIEWER_DOCUMENT_FOLDER</param-name>
<param-value>documents</param-value>
</context-param>
<context-param>
<description>Flag whether to allow server-side printing. Possible values are ON and OFF. Defaults to ON</description>
<param-name>BIRT_VIEWER_PRINT_SERVERSIDE</param-name>
<param-value>ON</param-value>
</context-param>
<context-param>
<description>Memory size in MB for creating a cube.</description>
<param-name>BIRT_VIEWER_CUBE_MEMORY_SIZE</param-name>
<param-value></param-value>
</context-param>
<context-param>
<description>Directory where to store all the birt report script libraries (JARs).. Defaults to ${Context Root}/scriptlib</description>
<param-name>BIRT_VIEWER_SCRIPTLIB_DIR</param-name>
<param-value>scriptlib</param-value>
</context-param>
<context-param>
<description>Temporary images/charts directory. Defaults to ${Context Root}/report/images</description>
<param-name>BIRT_VIEWER_IMAGE_DIR</param-name>
<param-value>report/images</param-value>
</context-param>
<context-param>
<description>BIRT viewer extended configuration file</description>
<param-name>BIRT_VIEWER_CONFIG_FILE</param-name>
<param-value>WEB-INF/viewer.properties</param-value>
</context-param>
<context-param>
<description>Preview report rows limit. An empty value means no limit.</description>
<param-name>BIRT_VIEWER_MAX_ROWS</param-name>
<param-value></param-value>
</context-param>
<context-param>
<description>Max cube fetch rows levels limit for report preview (Only used when previewing a report design file using the preview pattern). Defaults to return all levels</description>
<param-name>BIRT_VIEWER_MAX_CUBE_ROWLEVELS</param-name>
<param-value></param-value>
</context-param>
<context-param>
<description>Default locale setting</description>
<param-name>BIRT_VIEWER_LOCALE</param-name>
<param-value>en-US</param-value>
</context-param>
<context-param>
<description>Max cube fetch columns levels limit for report preview (Only used when previewing a report design file using the preview pattern). Defaults to return all levels</description>
<param-name>BIRT_VIEWER_MAX_CUBE_COLUMNLEVELS</param-name>
<param-value></param-value>
</context-param>
<context-param>
<description>Report resources(design files or document files) directory for preview. Defaults to ${Context Root}</description>
<param-name>BIRT_VIEWER_WORKING_FOLDER</param-name>
<param-value></param-value>
</context-param>
<context-param>
<description>Report Engine logs directory. Default to ${Context Root}/logs</description>
<param-name>BIRT_VIEWER_LOG_DIR</param-name>
<param-value>logs</param-value>
</context-param>
<context-param>
<description>Resource location directory (library files, images files or others). Defaults to ${Context Root}</description>
<param-name>BIRT_RESOURCE_PATH</param-name>
<param-value></param-value>
</context-param>
<context-param>
<description>Flag whether to force browser-optimized HTML output. Defaults to true</description>
<param-name>HTML_ENABLE_AGENTSTYLE_ENGINE</param-name>
<param-value>true</param-value>
</context-param>
<context-param>
<description>Report engine log level. (ALL|SEVERE|WARNING|INFO|CONFIG|FINE|FINER|FINEST|OFF)</description>
<param-name>BIRT_VIEWER_LOG_LEVEL</param-name>
<param-value>WARNING</param-value>
</context-param>
<listener>
<listener-class>org.eclipse.birt.report.listener.ViewerHttpSessionListener</listener-class>
</listener>
<listener>
<listener-class>org.eclipse.birt.report.listener.ViewerServletContextListener</listener-class>
</listener>
<servlet>
<servlet-name>EngineServlet</servlet-name>
<servlet-class>org.eclipse.birt.report.servlet.BirtEngineServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet>
<servlet-name>ViewerServlet</servlet-name>
<servlet-class>org.eclipse.birt.report.servlet.ViewerServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ViewerServlet</servlet-name>
<url-pattern>/frameset</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>EngineServlet</servlet-name>
<url-pattern>/document</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>EngineServlet</servlet-name>
<url-pattern>/download</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>EngineServlet</servlet-name>
<url-pattern>/parameter</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>EngineServlet</servlet-name>
<url-pattern>/extract</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>ViewerServlet</servlet-name>
<url-pattern>/run</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>EngineServlet</servlet-name>
<url-pattern>/preview</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>EngineServlet</servlet-name>
<url-pattern>/output</url-pattern>
</servlet-mapping>
<filter>
<filter-name>ViewerFilter</filter-name>
<filter-class>org.eclipse.birt.report.filter.ViewerFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>ViewerFilter</filter-name>
<servlet-name>EngineServlet</servlet-name>
</filter-mapping>
<filter-mapping>
<filter-name>ViewerFilter</filter-name>
<servlet-name>ViewerServlet</servlet-name>
</filter-mapping>
<servlet>
<servlet-name>JBoss BIRT Servlet</servlet-name>
<servlet-class>org.jboss.tools.birt.servlet.JBossBirtServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>JBoss BIRT Servlet</servlet-name>
<url-pattern>/embed</url-pattern>
</servlet-mapping>