Is there a work round?
I have some Ultegra wheels I think they are 9/10 speed hubs.
I found this whilst searching for info:
http://forum.bikerag.com/viewtopic.php?f=9&t=12256
This is possible, but you need a couple things:
1. New Shimano 8 speed cassette (recommend the Ultegra)
2. New 8 speed chain (SRAM 8 speed with masterlink is good)
3. Cassette spacer conversion from Quality Bike Parts (your LBS should have this in their catalog) for the Shimano to Campy conversion.
Once you have all this stuff you just install the new spacers, put on the new chain, lube and adjust, and ride into the sunset.
I know that this works well because I used to race a similar setup on a pair of Mavic Classic Pros that came with a Shimano only compatible spline for the 8 speed. It worked great, and continues to up until the present day.
As an aside, you may want to stock up on these parts because 8 speed stuff is getting pretty tough to find. I had to source a Campy cassette last spring when the drivetrain got all and skippy and it was a tough thing to do. Ultimately Nashbar had it but it was a pain.
Good luck!