I’ve had this issue on OSX Mavericks and Yosemite on soapUI 5.x versions. Here’s a fix that disables the browser in soapUI which seems to cause it to hang.
/Applications/SoapUI-5.2.0.app/Contents/ (adjust to suit your version).
vmoptions.txt and add line:
/Applications/SoapUI-5.2.0.app/Contents/java/app/bin (adjust to suit your version)
soapUI.sh and uncomment line: