I am just going to copy the infected(?) file onto a virtual machine and run an online scan to make sure it is a FP.
Not sure that I can create a custom file as I use ghost 2003 and backup the entire disk, this backup creates several 2GB .GHS files and only one or two of the set of 13 show as infected
Eg.
Set 1
D:\Ghost Images\Most Recent\18122009\18122001.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
D:\Ghost Images\Most Recent\18122009\18122003.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
D:\Ghost Images\Most Recent\18122009\18122005.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
D:\Ghost Images\Most Recent\18122009\18122008.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
D:\Ghost Images\Most Recent\18122009\18122010.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
Set 2
D:\Ghost Images\Most Recent\28032010\28032008.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
Set 3
D:\Ghost Images\Most Recent\11032010\11032008.GHS" is infected by "Win32:Hupigon-ONX [Trj]" virus
So the chances of producing a small image and it being flagged as a virus are quite low