mount root image gives error bad fs type

[Manu K. Mohan]

I downloaded the appscale image from the downloads page http://code.google.com/p/appscale/downloads/list. I have installed appscale tools 1.5 in Ubuntu 10.04

I am trying to mount the image in a temporary directory for changing the root password.

"sudo mount -o loop root.img tmpdir" gives the following error
mount: wrong fs type, bad option, bad superblock on /dev/loop0,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail or so

" dmesg | tail" gives the following
[87068.936572] JBD: no valid journal superblock found
[87068.936578] EXT3-fs: error loading journal.
[87147.790604] JBD: no valid journal superblock found
[87147.790610] EXT3-fs: error loading journal.
[87653.080107] VFS: Can't find ext3 filesystem on dev loop0.
[87670.239162] VFS: Can't find ext3 filesystem on dev loop0.
[87680.449154] VFS: Can't find ext3 filesystem on dev loop1.
[87684.139433] EXT4-fs (loop1): VFS: Can't find ext4 filesystem
[88892.747046] JBD: no valid journal superblock found
[88892.747049] EXT3-fs: error loading journal.

I got details about image file like this
"file root.img "
root.img: Linux rev 1.0 ext3 filesystem data, UUID=77ccdebb-451d-48ff-96b7-df07038b7d1d (large files)

Also
"fdisk -ul root.img "
Disk root.img: 0 MB, 0 bytes
255 heads, 63 sectors/track, 0 cylinders, total 0 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk root.img doesn't contain a valid partition table

Is everything fine with this image? How to fix this issue?