Your Casper Admin will be able to tell you if the policy is going to unicast or multicast the image.
One easily missed step in imaging in regards to Multicasting vs Unicasting is how the image is scanned in asr. Check out the man page for asr, specifically the --nostream section.
The default in Disk Utility is to apply the --nostream option, making the bit ordering optimized for unicasting. The default in calling asr from Terminal is to not apply --nostream, making the bit ordering optimized for multicasting. Either way, so long as the image is scanned the imaging process will work. If it is scanned wrong, it will still work but will take longer. I don't know if this is exactly what's causing your issue, but it might be a factor.
Question to the JAMFers: Do the Casper tools automatically rescan the image if a policy wants to deploy the .dmg differently than how the image was scanned for asr?
