wildfly8 can't identify port-offset

I installed wildfly8 and mod_cluster reference steps of https://docs.jboss.org/author/display/AS72/AS7+Cluster+Howto

The cluster contains four servers,start up with domain mode:
10.19.222.52:server1/server2
10.19.222.53:server3/server4
10.19.222.50:apache

But it only detects server1 and server3 which the port is 8009.
The port-offset is 100,it can't identify the other port(8109) for server2 and server4.
Search errorlog of Apache ,the proxy:AJP always acquired connection through initial AJP port(8009) defined in domain.xml.

[Fri Sep 13 21:07:40 2013] [debug] mod_proxy_cluster.c(773): ajp_cping_cpong: Done
[Fri Sep 13 21:07:40 2013] [debug] proxy_util.c(2029): proxy: ajp: has released connection for (10.19.222.52)
[Fri Sep 13 21:07:43 2013] [debug] proxy_util.c(2011): proxy: ajp: has acquired connection for (10.19.222.53)
[Fri Sep 13 21:07:43 2013] [debug] proxy_util.c(2067): proxy: connecting ajp://10.19.222.53:8009/ to 10.19.222.53:8009
[Fri Sep 13 21:07:43 2013] [debug] proxy_util.c(2193): proxy: connected ajp://10.19.222.53:8009/ to 10.19.222.53:8009
[Fri Sep 13 21:07:43 2013] [debug] mod_proxy_cluster.c(773): ajp_cping_cpong: Done
[Fri Sep 13 21:07:43 2013] [debug] proxy_util.c(2029): proxy: ajp: has released connection for (10.19.222.53)
[Fri Sep 13 21:07:45 2013] [debug] proxy_util.c(2011): proxy: ajp: has acquired connection for (10.19.222.52)
[Fri Sep 13 21:07:45 2013] [debug] proxy_util.c(2067): proxy: connecting ajp://10.19.222.52:8009/ to 10.19.222.52:8009
[Fri Sep 13 21:07:45 2013] [debug] proxy_util.c(2193): proxy: connected ajp://10.19.222.52:8009/ to 10.19.222.52:8009
[Fri Sep 13 21:07:45 2013] [debug] mod_proxy_cluster.c(773): ajp_cping_cpong: Done
[Fri Sep 13 21:07:45 2013] [debug] proxy_util.c(2029): proxy: ajp: has released connection for (10.19.222.52)
[Fri Sep 13 21:07:46 2013] [debug] mod_manager.c(1667): manager_trans STATUS
[Fri Sep 13 21:07:46 2013] [debug] mod_manager.c(2323): manager_handler STATUS processing: "JVMRoute=2644d861-0ead-352c-ba1e-619f1e1f25e8&Load=100"
[Fri Sep 13 21:07:46 2013] [debug] mod_manager.c(1404): Processing STATUS
[Fri Sep 13 21:07:46 2013] [debug] proxy_util.c(2011): proxy: ajp: has acquired connection for (10.19.222.53)
[Fri Sep 13 21:07:46 2013] [debug] proxy_util.c(2067): proxy: connecting ajp://10.19.222.53:8009/ to 10.19.222.53:8009
[Fri Sep 13 21:07:46 2013] [debug] proxy_util.c(2193): proxy: connected ajp://10.19.222.53:8009/ to 10.19.222.53:8009
[Fri Sep 13 21:07:46 2013] [debug] mod_proxy_cluster.c(773): ajp_cping_cpong: Done
[Fri Sep 13 21:07:46 2013] [debug] proxy_util.c(2029): proxy: ajp: has released connection for (10.19.222.53)
[Fri Sep 13 21:07:46 2013] [debug] mod_manager.c(2366): manager_handler STATUS OK
[Fri Sep 13 21:07:47 2013] [debug] mod_manager.c(1667): manager_trans STATUS
[Fri Sep 13 21:07:47 2013] [debug] mod_manager.c(2323): manager_handler STATUS processing: "JVMRoute=ea81701b-f847-34a8-9534-0ac5c489af90&Load=100"
[Fri Sep 13 21:07:47 2013] [debug] mod_manager.c(1404): Processing STATUS
[Fri Sep 13 21:07:47 2013] [debug] proxy_util.c(2011): proxy: ajp: has acquired connection for (10.19.222.52)
[Fri Sep 13 21:07:47 2013] [debug] proxy_util.c(2067): proxy: connecting ajp://10.19.222.52:8009/ to 10.19.222.52:8009
[Fri Sep 13 21:07:47 2013] [debug] proxy_util.c(2193): proxy: connected ajp://10.19.222.52:8009/ to 10.19.222.52:8009