The error message is the same for me. 

Here is my /var/log/dist-upgrade/main.log content :

2007-10-19 14:03:13,018 INFO release-upgrader version '0.81' started
2007-10-19 14:03:13,383 DEBUG lsb-release: 'gutsy'
2007-10-19 14:03:13,384 DEBUG _pythonSymlinkCheck run
2007-10-19 14:03:13,793 DEBUG checkViewDepends()
2007-10-19 14:03:13,793 DEBUG getRequiredBackports()
2007-10-19 14:15:29,364 ERROR IOError in cache.update(): 'Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/Release.gpg Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/main/i18n/Translation-fr.bz2 Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/restricted/i18n/Translation-fr.bz2 Échec de la connexion
Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/universe/i18n/Translation-fr.bz2 Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
'. Retrying (currentRetry: 0)
2007-10-19 14:21:10,540 ERROR IOError in cache.update(): 'Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/Release.gpg Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/main/i18n/Translation-fr.bz2 Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
'. Retrying (currentRetry: 1)
2007-10-19 14:30:54,343 ERROR IOError in cache.update(): 'Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/Release.gpg Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/main/i18n/Translation-fr.bz2 Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
Failed to fetch http://fr.archive.ubuntu.com/ubuntu/dists/gutsy/restricted/i18n/Translation-fr.bz2 Connexion à fr.archive.ubuntu.com: 80 (194.2.0.36) impossible, délai de connexion dépassé
'. Retrying (currentRetry: 2)
2007-10-19 14:30:54,343 ERROR doUpdate() failed complettely
2007-10-19 14:30:55,759 DEBUG marking 'release-upgrader-apt' for install
2007-10-19 14:30:55,801 DEBUG marking 'release-upgrader-dpkg' for install
2007-10-19 14:34:55,934 DEBUG pre-requists item: '<pkgAcquire::ItemIterator object: Status: 3 Complete: 0 Local: 0 IsTrusted: 1 FileSize: 1974216 DestFile:'/tmp/kde-steph/adept_managervSTiUa.tmp-extract/backports/partial/release-upgrader-dpkg_1.14.5ubuntu11.2_amd64.udeb' DescURI: 'http://fr.archive.ubuntu.com/ubuntu/pool/main/r/release-upgrader-dp' 
2007-10-19 14:34:55,934 DEBUG pre-requists item: '<pkgAcquire::ItemIterator object: Status: 3 Complete: 0 Local: 0 IsTrusted: 1 FileSize: 1312844 DestFile:'/tmp/kde-steph/adept_managervSTiUa.tmp-extract/backports/partial/release-upgrader-apt_0.6.46.4ubuntu10.3_amd64.udeb' DescURI: 'http://fr.archive.ubuntu.com/ubuntu/pool/main/r/release-upgrader-a' 
2007-10-19 14:34:55,935 ERROR no backports found but setupRequiredBackports() called??!

Here is my /var/log/dist-upgrade/apt.log content :

Error: "/var/tmp/kdecache-steph" is owned by uid 1000 instead of uid 0.