For clarification, this only represents the destination servers connected? I believe the user is under the impression that this metric should be showing him the current queue depth. Is there another JMX metric that would provide details on the queue depth?
Is that queue depth in relation to messages (MQ/JMS)? I found a few JBoss web references to "JMS queue depth"
As J-F said for JMX metrics the agent is only reporting the configured JMX attribute values as they are stored on JBoss, so going back to the original DestCount question to compare what agent is displaying with JBoss you can use jconsole to connect to JBoss and look at the values there.
Example within this KB: JMX in Jboss 7.x / jboss eap 6.x - CA Knowledge
Hope it helps.
Branched into a new question