Unpropagated Images appear to not have unique names

[buzztroll]

I noticed a name in the cumulus tree:

Repo__VMS__d840f8aa-f81e-11df-aba9-00215ec933e4__ubuntu10.10.bresnaha.gz

I would expect it to look more like:

tmpvN3xzzRepo__VMS__d840f8aa-f81e-11df-aba9-00215ec933e4__ubuntu10.10.gz

notice the bits at the beginning making it unique. This could result in bad things when images are propagated at the same time, or an unpropagated image fails halfway through.