After bugging Matt Zimmerman about this bug on IRC, he made a new build which could be OK for making this bug disappear.
I cannot test this myself now, but, Andrew, could you test yourself as you mentioned you werehit by it as well? The new APT is available at http://people.debian.org/~mdz/apt-0.5.27.2/ (i386 build) You probably to manually install it before running tasksel, for instance by switching to VT2 as soon as base-config starts. I'll make this test myself, but probably not before a few days. --
