Handling connectivity issues in web service outbound gateway (retry)

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Currently, we have a requirement to attempt a WS request, and in the case that the remote endpoint is down, queue the request for retry. This queue should also be backed by a database, so that if the application goes down, the requests will be retried once it is restarted.

I am hoping that I can achieve this purely with Spring Integration. My thought was that I could use a WS Outbound Gateway, with a message-store-backed queue channel set as the error channel. The error channel would be polled, and the message would be sent to a retry gateway (via Service Activator) which would also hook up to the WS Outbound Gateway, and basically form a processing loop.

The idea of the Service Activator and retry Gateway was taken from one of Oleg's SpringOne 2GX examples. The polling is happening properly, but I can't figure out how to "complete the loop" and actually get the retry to happen. Oddly, the poller seems to stop after the retry gateway is invoked.

Here is what I have currently:

        <!-- Will replace this with a JDBC store later -->
        <bean id="testMessageStore" class="org.springframework.integration.store.SimpleMessageStore" />

        <int:channel id="wsRequestChannel" />
        <int:channel id="wsReplyChannel" />
        <int:channel id="wsErrorChannel">
            <int:queue message-store="testMessageStore" />
        </int:channel>

        <int:channel id="testChannel" />
        <int:chain input-channel="wsErrorChannel" auto-startup="true">
            <int:poller fixed-rate="5000">
                <int:transactional transaction-manager="transactionManager" />
            </int:poller>
            <int:transformer expression="payload.getFailedMessage().getPayload() + ' '" />
            <!-- Everything seems to work fine up to here, but how do I get it to retry the WS? -->
            <int:service-activator ref="retryGateway" />
        </int:chain>

        <int:chain input-channel="wsRequestChannel" output-channel="wsReplyChannel">
            <int-ws:header-enricher>
                <int-ws:soap-action value="theTargetSoapAction" />
            </int-ws:header-enricher>
            <int-ws:outbound-gateway id="testWsGateway" uri="https://someSOAPService" interceptor="wsSecurityInterceptor" />
        </int:chain>

        <int:gateway id="mainGateway" default-request-channel="wsRequestChannel" default-reply-channel="wsReplyChannel" error-channel="wsErrorChannel" service-interface="com.mypackage.IntegrationTestService">
            <int:method name="sendMessage" />
        </int:gateway>
        <int:gateway id="retryGateway" default-request-channel="wsRequestChannel" default-reply-channel="wsReplyChannel" error-channel="wsErrorChannel" />

Can anyone help with this, or offer up suggestions for alternative approaches?
Thanks!