Aren't you supposed to run md5sum on the iso? It will then output a long string, you then match the string against the contents of the checksum text file that came with the iso.
For example, recently i downloaded FreeBSD..
$ md5sum 5.4-RELEASE-I386-disc1.iso
2afe65af7e7b994c3ce87cefda27352e
Now check it against the CHECKSUM.MD5 file here..
ftp://ftp.freebsd.org/pub/FreeBSD/re...SO-IMAGES/5.4/
Then again, maybe you are trying to do something i haven't done before, in which case my advice will be no use...lol.
Cheers