Hello,
Five months ago, I had a disk image size issue with virt-clone, the details are in the bug description:
https://bugzilla.redhat.com/show_bug.cgi?id=667509
I hope that someone try reproduce it.
Best regards.
There's no timeline for fixing Fedora bugs. You could try digging into the source yourself.
Feel free to follow up on our virt-clone survey though:
https://www.redhat.com/archives/virt-tools-list/2011-May/msg00019.html
Rich.