I added an illustrated step-by-step guide how to represent a problem,
with video. Can you please check this guide and specify that is the
difference between yours and my setups?

http://stackoverflow.com/questions/9063877/why-ruby-1-9-gui-hangs-if-i-do-any-intensive-computation-in-separate-ruby-thread

On Thu, Feb 23, 2012 at 5:09 AM, KOSAKI Motohiro
<kosaki.motohiro / gmail.com> wrote:
>> No, it fails same way on all my OSX versions from 10.5 to 10.7
>> Do you mean that you don't experience any difference resizing a Tk
>> window with worker thread started and without worker thread started?
>
> Sure. No difference.
>