I am not sure if I completely understand what you are trying to accomplish, but if you are trying to run all of them at once, with one execution, I'm not sure if the command line testrunner.bat tool can handle that scenario.
If it is not available via the command-line args, you could either put them all in an ant task (w/ properties files) or you could wrap them up in a shell script.
I assume you have looked at the docs:
http://www.soapui.org/userguide/command ... unner.htmlPlease elaborate on your question a little more.