partman blocks installer in alpha6

[Clemens Eisserer]

Hi,

I tried installing "Intrepid Alpha 6" on my laptop however I had the
following problems:

1. When booting directly in installation mode, X starts but then
nothing happens and ubiquity comsumes 99% cpu.
2. When booting as live-cd I can start the installer, but after step 4
or 5 when the small dialog shortly appears (contains only progressbar
I guess about partitioning), it also gets stuck.
The installer does not respond to clicks anymore, but this time also
no program creates heavy load.
Top shows some "partman" processes started, so I guess it has to do
something about partitioning.

Any ideas what could be the reson for this, and how can I get more
information about what goes wrong?
Is this already a known problem?

Thank you in advance,  Clemens