Why I am unable to upgrade from RHEV 3.0 to RHEV 3.1 Beta?

Issue

• While trying to upgrade from RHEV 3.0 GA to RHEV 3.1 Beta the following error messages are seen:

Loaded plugins: product-id, rhnplugin
Checking for updates... (This may take several minutes)
13 Updates available:
 * rhevm-3.1.0-12.el6ev.noarch
 * rhevm-backend-3.1.0-12.el6ev.noarch
 * rhevm-config-3.1.0-12.el6ev.noarch
 * rhevm-dbscripts-3.1.0-12.el6ev.noarch
 * rhevm-genericapi-3.1.0-12.el6ev.noarch
 * rhevm-iso-uploader-3.1.0-2.el6ev.noarch
 * rhevm-log-collector-3.1.0-2.el6ev.noarch
 * rhevm-notification-service-3.1.0-12.el6ev.noarch
 * rhevm-restapi-3.1.0-12.el6ev.noarch
 * rhevm-tools-common-3.1.0-12.el6ev.noarch
 * rhevm-userportal-3.1.0-12.el6ev.noarch
 * rhevm-webadmin-portal-3.1.0-12.el6ev.noarch
 * vdsm-bootstrap-4.9.6-28.0.el6_3.noarch
Error: JBoss service is dead, but pid file exists
Error: Upgrade failed.
please check log at /var/log/ovirt-engine/ovirt-engine-upgrade_2012_08_31_10_22_00.log