Hi,
The soapUI Runner in loadUI uses soapUI as a library when running a soapUI project, the difference lies in how load tests are managed. soapUI has a more simplistic threading model where each thread gets allocated up front and runs the TestCase the desired number of times. The actual handling of connections is done by HttpClient, a third party library. There is no code in soapUI to ensure your desired behavior, it seems like it's more of a fluke that it is working as you want it to. I'm not sure how HttpClient pools its connections (it's likely keeping one connection per thread), but it's likely that we could interface with it to ensure that the desired behaviour is achieved, though it may require a bit of effort, so please create a feature request detailing the exact behavior you would like to see and we'll see what we can do to accomodate it.
Regards,
Dain
SmartBear Software
