I've been using PING (which I understand uses Partimage under the covers) for a little while to back up an ext4 partition. I've just become aware that Partimage doesn't support ext4, so I'm confused as to why it appears to be working (although I've not tried to restore it).

The Disk Utility (version 2.30.1) on Ubuntu 10.10 reports the partition as Ext4 (version 1.0). However, PING and GParted report it as ext3fs. As far as I'm concerned it should be ext4 as that's what I selected during installation.

What's going on?