Roo hangs when shell is started in STS

Dear all
I have a project which was developed with Roo 1.1.0.
I now updated to latest
STS 3.0.0
Roo 1.2.2
JDK 1.7.0_07
(Windows 7 64 bit, 4GB RAM)

when I try to start the Roo Shell, the shell appears, a command can be typed in the textbox, but nothings results. The systems seams to be working (CPU > 20%), but after 10 minutes a typical command ("hint") is still not executed. The "Progress" view shows "Execute command 'hint' on project 'WebPortal' (Waiting)

I took a few stack traces which I attach (time between first and last ~14 minutes)

Any ideas on what to do. I can now only kill STS and restart.