release upgrade fails on Kubuntu Vivid 15.04 Beta 2

[Jonathan Riddell]

crashes.. log says

2015-03-25 20:31:00,028 ERROR got an error from dpkg for pkg: 'kubuntu-desktop': 'dependency problems - leaving unconfigured'
2015-03-25 20:31:00,061 DEBUG running apport_pkgfailure() kubuntu-desktop: dependency problems - leaving unconfigured
2015-03-25 20:31:00,069 DEBUG dpkg error because of dependency problems, not reporting against kubuntu-desktop
2015-03-25 20:31:00,069 ERROR got an error from dpkg for pkg: 'kubuntu-desktop': 'dependency problems - leaving unconfigured'
2015-03-25 20:56:16,724 WARNING no activity on terminal for 240 seconds (Installed xinit (amd64))
2015-03-25 20:56:30,221 ERROR not handled exception in KDE frontend:
Traceback (most recent call last):

  File "/tmp/ubuntu-release-upgrader-mme_sj3x/DistUpgrade/DistUpgradeViewKDE.py", line 151, in keyPressEvent
    os.write(self.installProgress.master_fd, ev.text().toUtf8())

AttributeError: 'str' object has no attribute 'toUtf8'

2015-03-25 20:56:30,221 DEBUG running apport_crash()
2015-03-25 20:56:45,678 ERROR not handled exception in KDE frontend:
SystemError: E:write, still have 80 to write but couldn't, E:Sub-process /usr/bin/dpkg returned an error code (1)

in /var/log/apt-term.log

Setting up xinit (1.3.4-1) ...
dpkg: dependency problems prevent configuration of kubuntu-desktop:
 kubuntu-desktop depends on baloo-kf5; however:
  Package baloo-kf5 is not installed.

dpkg: error processing package kubuntu-desktop (--configure):
 dependency problems - leaving unconfigured
Setting up kubuntu-settings-desktop (1:15.04ubuntu2) ...