mod_jk connection to JBoss fails with "All tomcat instances failed, no more workers left"

Issue

• After setting up Apache and mod_jk to connect JBosson a remote machine, the initial attempt to connect fails.  The following exceptions appear in the logs:

Trying ...
[debug] jk_ajp_common.c (3010): recycling connection pool slot=0 for worker node1
[debug] jk_lb_worker.c (1374): worker node1 escalating local error to global error
[info] jk_lb_worker.c (1388): service failed, worker node1 is in error state
[debug] jk_lb_worker.c (1399): recoverable error... will try to recover on other worker
[info] jk_lb_worker.c (1468): All tomcat instances are busy or in error state
[error] jk_lb_worker.c (1473): All tomcat instances failed, no more workers left
[info] mod_jk.c (2618): Service error=0 for worker=loadbalancer

• User has verified that JBoss is up, and that the jmx console is available from a browser running on that machine.