Comment 6 for bug 153926

Yes, exactley the same situation, however I am running a 32bit version of the OS.
After looking through the apt.log in /var/log/dist-upgrade I've noticed something that might be related to this:

...after installing and checking dependencies (files attached)

kdecore (KProcess): WARNING: setPty()
kdecore (KProcess): WARNING: _attachPty() 93
updateStatus: Reading cache
updateStatus: Checking package manager
updateStatus: Updating repository information
updateStatus: Checking package manager
updateStatus: Asking for confirmation
updateStatus: Fetching
updateStatus: Upgrading
updateStatus: Searching for obsolete software
Error in sys.excepthook:
Traceback (most recent call last):
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeViewKDE.py", line 460, in _handleException
    if not run_apport():
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeApport.py", line 44, in run_apport
    ret = subprocess.call(p)
  File "/usr/lib/python2.5/subprocess.py", line 443, in call
    return Popen(*popenargs, **kwargs).wait()
  File "/usr/lib/python2.5/subprocess.py", line 593, in __init__
    errread, errwrite)
  File "/usr/lib/python2.5/subprocess.py", line 1061, in _execute_child
    self.pid = os.fork()
OSError: [Errno 12] Cannot allocate memory

Original exception was:
Traceback (most recent call last):
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/dist-upgrade.py", line 59, in <module>
    app.run()
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeControler.py", line 1346, in run
    self.fullUpgrade()
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeControler.py", line 1335, in fullUpgrade
    self.doPostUpgrade()
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeControler.py", line 945, in doPostUpgrade
    res = self.cache.commit(fprogress,iprogress)
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeCache.py", line 69, in commit
    apt.Cache.commit(self, fprogress, iprogress)
  File "/usr/lib/python2.5/site-packages/apt/cache.py", line 203, in commit
    if fetchProgress == None:
  File "/usr/lib/python2.5/site-packages/apt/cache.py", line 178, in installArchives
    # this can throw a exception
  File "/usr/lib/python2.5/site-packages/apt/progress.py", line 213, in run
    pid = self.fork()
  File "/tmp/kde-root/adept_managerfpj1ca.tmp-extract/DistUpgradeViewKDE.py", line 244, in fork
    self.child_pid = os.fork()
OSError: [Errno 12] Cannot allocate memory
X Error: BadDevice, invalid or uninitialized input device 158
  Major opcode: 150
  Minor opcode: 3
  Resource id: 0x0
Failed to open device
X Error: BadDevice, invalid or uninitialized input device 158
  Major opcode: 150
  Minor opcode: 3
  Resource id: 0x0
Failed to open device
adept_manager: no process killed
adept_updater: no process killed
Starting
Starting 2
Done
MarkUpgrade() called on a non-upgrable pkg: 'kubuntu-desktop'
Error: "/var/tmp/kdecache-kosio" is owned by uid 1000 instead of uid 0.
updateStatus: Reading cache
updateStatus: Checking package manager
updateStatus: Updating repository information
updateStatus: Checking package manager
updateStatus: Asking for confirmation
updateStatus: Restoring original system state