ls -laF /var/lib/amanda/normal/index/hostname
drwxr-sr-x  2 amanda disk 4096 Sep 13 16:56 _/
drwxr-sr-x  4 amanda disk 4096 Sep 13 16:47 ./
drwxr-xr-x  4 amanda disk 4096 Sep 13 16:24 ../

I have checked the logfiles and they seem fine:
START driver date 20050913
DISK planner hostname /
START planner date 20050913
WARNING planner tapecycle (3) <= runspercycle (10)
FINISH planner date 20050913
STATS driver startup time 0.387
START taper datestamp 20050913 label Normal-01 tape 0

INFO taper tape Normal-01 kb 288 fm 1 [OK]
FINISH driver date 20050913 time 35.101

I have the following setup:

/etc/normal/amanda.conf (some entries excluded)
dumpuser "amanda"
infofile "/var/lib/amanda/normal/curinfo" # database filename
logdir   "/var/lib/amanda/normal"  # log directory
indexdir "/var/lib/amanda/normal/index" # index directory
tapelist "/var/lib/amanda/normal/tapelist"
define dumptype global {
   comment "Global definitions"
}
define dumptype root-tar {
   global
   program "GNUTAR"
   comment "root partitions dumped with tar"
   compress none
   index yes
   priority low
}

/etc/normal/disklist.conf
hostname / {
  root-tar
  include "./etc"
}

Regards