It is a common way to interconnect Apache and Java application servers (Tomcat, JBoss, Jetty, Glassfish and others) by utilizing the AJP protocoll.
When trying to tweak configurations to handle a large number of concurrent requests it may happen, that responses are mixed-up behind your Apache server. In this case you will notice a number of responses that do not match the associated requests.
In this case you should take a look at the configuration of your AJP connector within the Apache server. The default configuration file is named 'workers.properties'. To fix your problem you have to initialize the parameter 'connection_pool_size' correctly. You have to assign the value of '1' or comment it out.
The following example shows you how to setup the file 'workers.properties' with a minimum set of options.
# path separator ps=/ # list of workers worker.list=mount-id # set worker properties worker.mount-id.type=ajp13 worker.mount-id.host=localhost worker.mount-id.port=8123 worker.mount-id.connection_pool_size=1