I could also observe crash every time I run the test.
Just in case, i attached simple test case - maybe someone will
find it useful to reproduce the problem outside JCK framework
(the test just makes visible the page dialog two times).
Apparently, there are two things we can do with the problem.
1) evidently, crash happens in MSCTF.dll (MS is responsible for the library).
I believe that any native application (without Java code)
which deals with page dialog will fail in the same way.
I'm going to write simple native test. Perhaps, it's a bug for MS
(it looks like incompatibility in Vista).
2) the test works fine on JDK6.0. (at least, no crash occurs on
my environment). It indicates that there is some workaround of the
problem which we can possibly use to fix the problem in next update release
of JDK5.0. I could suggest that it may be related to modality improvements
in JDK6.0 somehow because the test fails inside ::SetForegroundWindow. But I may be
wrong, I had a very quick look.