Comment 3 for bug 880984

Note a few things:
a.) /dev/vda has has been grown during first boot, its partition table rewritten
   GROWROOT: CHANGED: partition=1 start=16065 old: size=4176900 end=4192965 new: size=20948760,end=20964825

   $ sudo sfdisk -g /dev/vda
   /dev/vda: 20805 cylinders, 16 heads, 63 sectors/track
   $ sudo sfdisk -l -uS /dev/vda

   Disk /dev/vda: 20805 cylinders, 16 heads, 63 sectors/track
   Warning: The partition table looks like it was made
     for C/H/S=*/255/63 (instead of 20805/16/63).
   For this listing I'll assume that geometry.
   Units = sectors of 512 bytes, counting from 0

      Device Boot Start End #sectors Id System
   /dev/vda1 * 16065 20964824 20948760 83 Linux
   /dev/vda2 0 - 0 0 Empty
   /dev/vda3 0 - 0 0 Empty
   /dev/vda4 0 - 0 0 Empty

b.) this does not occur for the ext3 (not ext4) filesystem on /dev/vdb
c.) this same error does not occur on oneiric