Comment 6 for bug 164507

> I have marked this as Low, as I doubt there will be many trying to chmod a fat32 partition.

 The usual situation for me was cp -a foo/*.mp3 /mnt/sd-usb/audiobooks/
cp -a would print an error as it tried to chown every file, although setting the mod time succeeded.
With Jaunty, tt doesn't print that error anymore. I tried with a real SD card in my USB reader, instead of using the loopback test I did before. Although I'm not using gnome or KDE with their device managers. My results differ from yours, Teej, so it's either device managers mounting with different options, or the kernel in Karmic returns errors for more cases than Jaunty. My kernel is built from Jaunty sources, but with my own config:
Linux version 2.6.28-15-tesla (root@tesla) (gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) ) #52 SMP Fri Aug 28 19:19:22 ADT 2009

 I wouldn't be surprised if Karmic is noisier, since some things that Jaunty doesn't return an error for should probably only be that way with mount -o quiet.

> Even by Windows standards, ntfs is the current one.

 fat is what you'll find on most flash-based removable storage (sd cards, USB flash drives, digital audio players, etc.).

 BTW, coreutils version doesn't matter. All versions of cp and esp. chmod will make the same system calls and report any errors that are returned. The variation will all be in what the kernel decides to return when you ask it do do something that FAT doesn't support. Mapping the Unix permission model onto FAT is the tricky part, and that code is all in the kernel. (in fs/fat/*, to be specific)