UDIF-CRC32 on Disc via Command Line or Apple Script

hi all

this is my first post (newbe).

i was asked by a friend to write an apple script that would run a virus check and a check sum on a CD/DVD.

Now i have the script running the Viruscheck, that was easy enough but im having a problem running the checksum on the disc can anyone help.

i have tried hdiutil checksum command which works great on a disk image but will not run on a disc media.

the Disk utilty runs the checksum on a disc but i cannot call it threw the script.

can anyone help.

the disc should always be in /dev/disk1s1

thanks in advance.

Model: mac mini
AppleScript: version 1
Operating System: Mac OS X (10.4)