After enabling event logging in the RHQ Agent Resource's conn props for both Agent logfiles, I restarted the PC from the Agent prompt. I saw the following exception in the Agent log:

[RHQ Agent Prompt Input Thread] (rhq.core.pc.inventory.InventoryManager)- Exception thrown while activating [Resource[id=10002, type=RHQ Agent, key=jetengine RHQ Agent, name=RHQ Agent, parent=jetengine, version=4.2.0.JON300.CR2]].
org.rhq.core.clientapi.agent.PluginContainerException: Failed to start component for resource Resource[id=10002, type=RHQ Agent, key=jetengine RHQ Agent, name=RHQ Agent, parent=jetengine, version=4.2.0.JON300.CR2].
	at org.rhq.core.pc.inventory.InventoryManager.activateResource(InventoryManager.java:1601)
	at org.rhq.core.pc.inventory.InventoryManager.activateAndUpgradeResourceRecursively(InventoryManager.java:2825)
	at org.rhq.core.pc.inventory.InventoryManager.activateAndUpgradeResourceRecursively(InventoryManager.java:2827)
	at org.rhq.core.pc.inventory.InventoryManager.activateAndUpgradeResources(InventoryManager.java:2785)
	at org.rhq.core.pc.inventory.InventoryManager.initialize(InventoryManager.java:231)
	at org.rhq.core.pc.PluginContainer.startContainerService(PluginContainer.java:431)
	at org.rhq.core.pc.PluginContainer.initialize(PluginContainer.java:282)
	at org.rhq.enterprise.agent.AgentMain.startPluginContainer(AgentMain.java:1870)
	at org.rhq.enterprise.agent.promptcmd.PluginContainerPromptCommand.execute(PluginContainerPromptCommand.java:61)
	at org.rhq.enterprise.agent.promptcmd.PluginsPromptCommand.executePCCommand(PluginsPromptCommand.java:267)
	at org.rhq.enterprise.agent.promptcmd.PluginsPromptCommand.doUpdate(PluginsPromptCommand.java:225)
	at org.rhq.enterprise.agent.promptcmd.PluginsPromptCommand.execute(PluginsPromptCommand.java:72)
	at org.rhq.enterprise.agent.AgentMain.executePromptCommand(AgentMain.java:2860)
	at org.rhq.enterprise.agent.AgentMain$5.run(AgentMain.java:2768)
	at java.lang.Thread.run(Thread.java:662)
Caused by: org.rhq.core.pc.inventory.TimeoutException: [Warning] Call to [org.rhq.plugins.agent.AgentServerComponent.start()] with args [[org.rhq.core.pluginapi.inventory.ResourceContext@6c5070c1]] timed out. Invocation thread will be interrupted
	at org.rhq.core.clientapi.agent.PluginContainerException.wrapIfNecessary(PluginContainerException.java:69)
	at org.rhq.core.clientapi.agent.PluginContainerException.<init>(PluginContainerException.java:96)
	... 15 more

Currently, InventoryManager.COMPONENT_START_TIMEOUT is set to 60 seconds. I'm thinking we should increase this to at least 120 seconds for server and platform Resources, which may need to start event logging and initiate various connections in their start() impls.