Thanks for the feedback all!

dws: I can't rename the files, 'cause part of the information I'm collecting (in the larger script) is the last modified time. I guess I could copy the file to a temp file with a reasonable name, but that could be trouble with very large files.

BrowserUK: Good call! I think it might be hitting cygwin. I'll have to try it on a Win2K box without cygwin tools installed.

traveler: I tried embedding the quotes, but it didn't change the result. I think it might be the shell env.

pg: It's not just echo, other commands do it too. Any command called straight from the shell works fine, but only when they're called from open does this happen.

More testing to come (tomorrow). I'll let you know if I find anything!