Folder copying problem in Tiger

I’m working on an update of an AppleScript application for Tiger, and I’m running into a rather puzzling problem. My application copies folders from one location to another for the purpose of making backups. In Panther and earlier OS X versions, I had no problem with scripted copying operations ” but in Tiger, for some reason that I haven’t been able to pin down, all of the folders that I’m working with copy fine, with the sole exception of the ~/Library/Mail folder. The script gives every indication of preparing for the copy, but when the time for the actual copying comes, all of a sudden the script skips to the next step without copying anything. I’ve checked to see if it encounters an error, but the error check shows nothing. A check of the owner/privileges settings shows nothing that would prevent copying ” but inexplicably, it’s no go. Has anyone else encountered a situation like this, and if so, how, if at all, have you solved it?

you though of trying

do shell script "ditto ~/Library/Mail /volume/disk

or whereever you you save it to