from here: VMware takes aim at mission-critical workloads with vSphere 5.5
App HA uses VMware vFabric Hyperic to monitor supported applications inside those VMs and detect application failures, even if the VM continues to run. If it detects an application failure, it can automatically restart the application, or if an application fails to start, reset the VM. App HA and the Hyperic components it relies on will now be included with vSphere Enterprise Plus.