Comment 4 for bug 280660

Just installing Lenny's apt over does not work, as it is linked to libc6 2.7 instead of 2.8whatever that intrepid uses, so it doesn't have the necessary files in /usr/lib (such as installing /usr/lib/libapt-pkg-libc6.7-6.so.1.1 instead of libc6.8 ) , regardless of ABI breakage. Pity :(

Latest apt and related apps should be backported IMHO, as this is a serious bug that bites anyone trying to track two distros at the same time (and using apt_preferences to avoid ruining the system while doing so).