Duplicate session error when perform proxy lookup

We have deployed a flex application on Tomcat and it uses Blaze-DS to communicate with the Java side. However when using the deployed application we constantly get the error:

Detected duplicate HTTP-based FlexSessions, generally due to the remote host disabling session cookies. Session cookies must be enabled to manage the client connection correctly. url: 'http://XX.XX.XXX.XXX:80/CB3/SdmxSandbox/messagebroker/amf;jsessionid=2A71A4A58872C757B9064D20C9E876D9''

I don't understand what is causing this or what this error really means? Can anyone help?

Further detail:

Within our Apache httpd.conf we have set up a proxy lookup so that rather than using particular ports (e.g 8082) we want to use port 80 (some of our customers operate in a locked-down environment). So the httpd.conf file looks like:

ProxyPass        /CB3/ http://XX.XX.XXX.XXX:8082/
ProxyPassReverse /CB3/ http://XX.XX.XXX.XXX:8082/

Now we didn't get the Duplicate Session issue until we introduced the prox开发者_如何学编程y redirect. My services-config is fairly straightforward:

<?xml version="1.0" encoding="UTF-8"?>
<services-config>

<factories>
    <factory id="spring" class="flex.messaging.factory.SpringFactory" />
</factories>


<services>
    <service-include file-path="remoting-config.xml" />

    <default-channels>
        <channel ref="my-amf" />
    </default-channels>
</services>

<channels>
    <channel-definition id="my-amf"
        class="mx.messaging.channels.AMFChannel">
        <endpoint
            url="http://{server.name}:{server.port}/{context.root}/messagebroker/amf"
            class="flex.messaging.endpoints.AMFEndpoint" />
    </channel-definition>
</channels>

Any help greatly appreciated.

Thanks,

Phil

The duplicate session message is a known problem, and it can appear from several reasons. I'm not able to tell you what is the reason in your case, but I'll wrote down the best articles dealing with this issue.

http://www.alexglosband.com/?p=3

http://meteatamel.wordpress.com/2011/01/26/duplicate-session-errors-in-lcdsblazeds/

http://blogs.adobe.com/lin/2011/05/duplication-session-error.html