Crashes when loading partitioner

Binary package hint: ubiquity

Am I using a recent (post Herd 3, featuring the migration assistant) Feisty Live CD.

The problem is that ubiquity keeps crashing when starting the advanced/manual partitioner.
It displays the progress bar that says "scanning hard drives" or something, this seems to complete, then it goes away and ubiquity sits there (though the GUI is still somehow responsive and I can use the cancel button to close it), and there is the "bomb" icon in the notification area. I click on it, it says Ubiquity crashed, I proceed to report the problem, it collects data, indicates that it uploads them to launchpad and... well and that's it. Apport doesn't start the web browser or anything, I am left wondering what to do next. I don't know if the crash data have actually been uploaded for real, in which case they must be polluting launchpad since they aren't attached to any bug report !

So, where does apport put its crash data, so I can attach them manually to this bug report ?
In the meantime I will attach syslog and partman log files.