Vivid Daily 20150315: Live cd does not boot in VirtualBox

Screenshot with altered boot options: Removed "quit" and "splash".

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Export mode on, acpi=off, removed "quit" and "splash".

Problem still present in Daily 20150317 but with slightly different output.
Screenshot attached.

Screenshot with altered boot options: Removed "quit" and "splash".

Booting into runlevel 1 works.
If anyone has an idea how to save the contents of journalctl -xb I will post them.

Problem also exists in Kubuntu Daily 20150317 i386.

Looking at lots it seems ubiquity-dm is failing because X just doesn't want to start.

Trying with ubuntu daily-live current (which is from March 6th) it starts X successfully but it doesn't show ubquity-dm and it uses upstart not systemd-sysv so that's not much of a metric.

Trying with ubuntu's daily-live pending (from today) it doesn't start X similar to Kubuntu so I think this is not a specific Kubuntu problem.

Problem also exists in Kubuntu Daily 20150318 i386.

Are you sure this is related to the X server? When I remove the maybe-ubiquity the problem does not disappear.

Sorry, I mistyped: Correct is "Kubuntu Daily 20150318 amd64".

Status changed to 'Confirmed' because the bug affects multiple users.

Kubuntu Daily 20150324 amd 64 seems to have this bug fixed.

@Jonathan Riddell: Were can I see the fix? I'm interested to see what went wrong ...