Permissions and owner/group changed when editing using gedit

This is an issue that is introduced in Gutsy, but worked correctly in Feisty.

Steps to reproduce the problem: enter following code in terminal, when gedit appears, type something, exit while saving.

mkdir test; cd test; touch test
sudo chown root:video test
sudo chmod 660 test
ls -l
gedit test
ls -l

A normal user is by default member of the video group, and therefore can edit the file test. On Feisty, the permissions are correctly retained when the normal user has edited the file:

-rw-rw---- 1 root video 5 2007-10-14 15:55 test
-rw-r----- 1 vanadium video 0 2007-10-14 15:55 test~

However, two users of Gutsy report a different behaviour:

-rw------- 1 rfb rfb 6 2007-10-13 19:32 test
-rw-rw---- 1 root video 0 2007-10-13 19:31 test~

Indeed, the backup has the original permissions, but permissions and owner are changed for the edited version. This obviously cripples the concept of unix permissions and will result in eventual hard links to point to the backup file instead of the updated file. As far as my technical skills go, this must be no more than a gedit issue, where gedit now saves the new content in a new inode (renaming afterwards) instead of saving to the same inode, as it should to maintain the integrity of the file management.