For performing any kind of installation; we always recommend that you should follow the installation manual of that particular product available at http://docs.redhat.com for JBoss Enterprise Webserver installation you can use the installation manual available here
Supported connectors and entitlements needed for availing support.
Red Hat only certifies and supports the connectors provided with JBoss Enterprise Web Server (EWS), JBoss Enterprise Application Platform (EAP) and JBoss Enterprise Web Platform (EWP) " on http://www.jboss.com/products/platforms/application/supportedconfigurations/
For details regarding the subscriptions needed for availing support you can refer the below kbase article
Configuring and optimizing EWS with JBoss
There are various connectors available which you can use for configuring EWS with JBoss.
If you are using a clustered JBoss environment and want to setup a loadbalanced environment using EWS then mod_cluster is the best and recommended option, mod_cluster is more efficient and robust in clustered environments as compared to conventional connectors such as mod-jk and mod-proxy. For more details regarding of benefits of mod_cluster you can refer http://www.jboss.org/mod_cluster
For configuring mod-cluster you can refer the below knowledgebase article.
mod-jk & mod-proxy
For configuring mod-jk and mod-proxy you can refer our HTTP Connectors Load Balancing Guide
Majority of issues related to connectors such as session issues/timeouts can be resolved by optimizing the existing configurations taking into account your underlying hardware. So i recommend that you should use the listed application  for optimizing the configurations. This community application generates fairly optimized configurations.
For a detailed explanation for optimization and troubleshooting , you can refer the below knowledgebase article
If the issue still persists even after optimizing your configurations , i would recommend to open a support case with us with the description of issue you are facing and attaching all the relevant log and configuration files.