Comment 10 for bug 63693

Pre-releases of dapper did this (base-installer), but final dapper wasn't supposed to. It does:

                if [ -n "$ramdiskconf" -a "$resume" ]; then
                        if [ "$package" = initramfs-tools ]; then
                                mkdir -p /target/etc/mkinitramfs/conf.d
                                echo "RESUME=$resume" > /target/etc/mkinitramfs/conf.d/resume
                        elif [ -f $ramdiskconf ] ; then
                                sed -e "s@^#* *RESUME=.*@RESUME=$resume@" < $ramdiskconf > $ramdiskconf.new &&
                                        mv $ramdiskconf.new $ramdiskconf
                        else
                                echo "RESUME=$resume" >> $ramdiskconf
                        fi
                fi

$package will always be initramfs-tools for us.

Note that initramfs-tools' maintainer scripts mangle the RESUME setting too, but I just checked dapper's version and it appears to be correct. So, I'm not sure what was at fault here.