I can confirm this bug on ubuntu 10.10 i368 update-manager: version 0.142.19 Linux ubuntu 2.6.35-22-generic #33-Ubuntu SMP Sun Sep 19 20:34:50 UTC 2010 i686 GNU/Linux
Synaptic can access updates, yet update-manager produces an error.
I can confirm this bug on ubuntu 10.10 i368
update-manager: version 0.142.19
Linux ubuntu 2.6.35-22-generic #33-Ubuntu SMP Sun Sep 19 20:34:50 UTC 2010 i686 GNU/Linux
Synaptic can access updates, yet update-manager produces an error.