kubuntu feisty->gusty alternate cdrom update crashes

Binary package hint: update-manager

Update Manager crashes after 99% of item "Installing Packages" . I didn't find exactly this bug report, so I report it in the hope that it might help. My machine has 786MB ram, 494MB swap.

Here is the error report:

Traceback (most recent call last):
  File "/tmp/tmpOV9nfp/gutsy", line 59, in <module>
    app.run()
  File "/tmp/tmpOV9nfp/DistUpgradeControler.py", line 1346, in run
    self.fullUpgrade()
  File "/tmp/tmpOV9nfp/DistUpgradeControler.py", line 1328, in fullUpgrade
    if not self.doDistUpgrade():
  File "/tmp/tmpOV9nfp/DistUpgradeControler.py", line 798, in doDistUpgrade
    res = self.cache.commit(fprogress,iprogress)
  File "/tmp/tmpOV9nfp/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
    res = self.installArchives(pm, installProgress)
  File "/usr/lib/python2.5/site-packages/apt/cache.py", line 178, in installArchives
    res = installProgress.run(pm)
  File "/usr/lib/python2.5/site-packages/apt/progress.py", line 213, in run
    pid = self.fork()
  File "/tmp/tmpOV9nfp/DistUpgradeViewKDE.py", line 244, in fork
    self.child_pid = os.fork()
OSError: [Errno 12] Cannot allocate memory

I can also provide the main.log and apt.log.