When I create a domain class and after that I create the same class again, the IDE remains focused in the details screen of the domain class but in the output there is a question (overwrite the old class...) that I can't answer. The solution is to kill netbeans process.
Product Version = NetBeans IDE 6.9 RC2 (Build 201005312001)
Operating System = Mac OS X version 10.6.4 running on x86_64
Java; VM; Vendor = 1.6.0_20
Runtime = Java HotSpot(TM) 64-Bit Server VM 16.3-b01-279
Similar things happen whenever you use the NetBeans wizard dialog to invoke a grails script that asks a question that needs interactively answering, e.g. because the file already exists and it wants to know if it should be overwritten. In 6.9 it does this by freezing with the wizard progress bar at 90% for me. There is nothing at all on the screen to suggest that it's waiting for input (in my experience anyway) and it's only because I ran the same command from a command line that I realised what was happening. I had to force quit NetBeans.
*** This bug has been marked as a duplicate of bug 187318 ***