Why do I get XML errors when I start system-config-cluster after adding a DRAC fence device?

When a DRAC (Dell Remote Access Card) is assigned as a cluster node's fence device using system-config-cluster, an attribute called modulename is added to the cluster configuration file. This attribute is only necessary for DRAC/MC (Modular Chassis) cards and should specify the node's hostname. However, even when the DRAC/MC option is left unchecked, which is the default, the attribute is stil...