Timing of ebXML Acknowledgements with Reliable Delivery

Hi

We have an implementation of webMethods where we route xml documents to participants via a hub. We send the documents using the wm.ip.ebXML.MSH:send service, with the following:
Delivery Method = ebXMLReliableDelivery
Retry Limit = 2
Retry Factor = 1
Wait Between Retries = 3,600,000
Delivery Semantics = OnceAndOnlyOnce

The issue I’m having is that when I view the activity log I find that an error is logged 1 second after the start of the delivery task (as it has not received an acknowledgement). The ebxml acknowledgement is typically received from the hub between 4 and 120seconds later. However, the task stays open (PENDING status) until one hour later (retry factor) when it attempts to send again. It then updates the status to DONE as the acknowledgement has been received.

I think this is causing sessions to remain open and therefore occupy both sessions and memory.

Is there a configuration setting somewhere that I can use to delay the initial check for an acknowledgement (appears to currently be 1 second) to approx 120 seconds?

Or perhaps there is a config setting that forces the task to be completed on receipt of the acknowledgement - instead of after the retry factor has lapsed?

Any help (I’m a bit of a newbie) would be appreciated.

Regards
Rob