sopaui 4.0.1 repeated calls while waiting for response

I'm testing a really long running service (more than 11mins) For this reason I incremented both the request and socket timeout.
Looking at the http-log (and on my application) I noticed that SoapUI continue to call the service after about every 40-50 seconds while waiting for the response (that never comes because of the overloading of the server)
Didn't found any options to change that behaviour, that really seems a bug to me.
Let me know and tnx in advance.