soapUI 4.0.0 and ASP.NET 4.0/javascript/postbacks/VIEWSTATE

I've used soapUI and loadUI to do basic functional and load tests with SOAP on Apache(LAMP), and it's worked great.

I'm now trying to use soapUI with a Microsoft IIS website written in ASP.NET 4.0. The initial screen of this website has a simple username and password field, along with a "Login" button.

After selecting a New soapUI project, entering the project name, selecting "Create Web TestCase", and entering the URL on the next screen, the website page is displayed, but I simply cannot click into the User Name or Password fields(ie cannot get focus with blinking cursor) --- and subsequently can't enter these values.

When I look at the html source for the page, I'm definitely seeing things like javascript, a function __doPostBack(), and the VIEWSTATE.

Is soapUI and web recording inherently incompatible with this type of setup?

UPDATE: There are other people having the same problem here. http://www.soapui.org/forum/viewtopic.php?f=5&t=7884&sid=ccdc286c82394b3989a450b906744e73

UPDATE2: More people with problems. http://www.eviware.com/forum/viewtopic.php?f=5&t=8005
sounds similar here too. http://orgwww.soapui.org/forum/viewtopic.php?f=5&t=8356

Thanks
Keith