Comment 2 for bug 215346

Here's the relevant chunks of main.log. if you want more, I can certainly get it to you.

2008-04-16 12:46:42,508 INFO release-upgrader version '0.87.18' started
2008-04-16 12:46:42,510 DEBUG Using 'DistUpgradeViewText' view
2008-04-16 12:46:42,796 DEBUG lsb-release: 'dapper'
2008-04-16 12:46:42,796 INFO using backports in '/tmp/tmpg-bY2r/backports'
2008-04-16 12:46:42,797 DEBUG have: ['/tmp/tmpg-bY2r/backports/release-upgrader-dpkg_1.14.5ubuntu11.6_ia64.udeb', '/tmp/tmpg-bY2r/backports/release-upgrader-apt_0.7.9ubuntu2_ia64.udeb']
...
2008-04-16 12:46:46,812 DEBUG Obsolete:
2008-04-16 12:46:46,813 DEBUG updateSourcesList()
2008-04-16 12:46:46,850 DEBUG rewriteSourcesList()
2008-04-16 12:46:46,852 DEBUG examining: 'deb http://ports.ubuntu.com/ubuntu-ports dapper main universe'
2008-04-16 12:46:46,860 DEBUG entry '# deb http://ports.ubuntu.com/ubuntu-ports dapper main universe' was disabled (unknown mirror)
2008-04-16 12:46:46,860 DEBUG examining: 'deb http://ports.ubuntu.com/ubuntu-ports dapper-updates main universe'
2008-04-16 12:46:46,867 DEBUG entry '# deb http://ports.ubuntu.com/ubuntu-ports dapper-updates main universe' was disabled (unknown mirror)
2008-04-16 12:46:46,867 DEBUG examining: 'deb http://ports.ubuntu.com/ubuntu-ports dapper-security main universe'
2008-04-16 12:46:46,874 DEBUG entry '# deb http://ports.ubuntu.com/ubuntu-ports dapper-security main universe' was disabled (unknown mirror)
2008-04-16 12:46:46,875 DEBUG examining: 'deb http://archive.admin.canonical.com/ dapper-cat main'
2008-04-16 12:46:46,882 DEBUG entry '# deb http://archive.admin.canonical.com/ dapper-cat main' was disabled (unknown mirror)
2008-04-16 12:46:46,882 ERROR No valid mirror found