Experience with a SD to Compact Flash card apapter in a DSLR?

So I've been lusting over one of these new Eye-Fi SD cards, and was bummed to find out that they are currently not available in Compact Flash format. Then I found some cheap (~$20) adapters, in which an SD card slides inside a Compact Flash blank, and could then presumably slide into my EOS 40D.


Does anyone have any experience with this? Does it even work with EOS DSLRs? I don't mind throwing away $20 to test the theory, but I don't want to drop ~$200 on the Eye-Fi card and then find out it isn't compatible.


Any real world experience, or knowledge of this scenario would be greatly appreciated. Also, if you know anything about the future of Compact Flash Eye-Fi cards, or future SD capable XXD EOS DSLRs (I've heard the 60D might offer this), I'd be interested in hearing about that, too.


Thanks!

I can tell you that the sd-cf adapters DO NOT work in the Nikon D1, D1h, or D1x bodies. I can also tell you that they DO WORK in the Canon 1d, D30, and 30D bodies. I have direct experience with all 6 of these bodies (I own Nikon, and my wife owns the Canons). Since the 40d is even newer technology than the 30d, I'm pretty confident that they will work just fine. Good luck and let me know.