According to a reported bug, Apple Mac OS X Lion client and server have trouble with Windows Sharing for flies including extended attributes. The issue extends to Windows 7 and Windows XP.
Steve Maser, senior systems administrator at the Univ. of Michigan's Office of Technology Transfer, posted the report to the Mac OS X Server list on Monday.
It will appear to start to copy down, but then you'll get a (more commonly for me) "the file name you specified is not valid or too long" error message or (less commonly in my case) an "Invalid MS-DOS Function" message.
Some of the types didn't always cause the problem, so Maser speculated that it isn't the fault of the attribute but its contents that cause it.
But, unless you remove the meta data, you won't be able to copy the file down to your Windows desktop. But you can open/run/delete/move the files without issue.
He offered a non-fix fix.
The problem is that *this doesn't solve the problem*. It only clears the metadata when you run the command. If you download another file from the internet or receive an e-mail attachment or take another screen shot (for example)? That metadata gets put back on the file and you are back in the the same boat.
Other posts in the discussion thread suggest that there are similar issues with other files. It appears that the early release of Lion Server is a work in progress, perhaps not the best choice for your prime-time use.