Who changed the system sounds in 8.10 to .ogg format, when the system will only accept .wav?

Thank you for taking the time to report this bug and helping to make Ubuntu better. Ubuntu 8.10 does play the OGG files perfectly fine for me. I hear the desktop-login.ogg sound when logging in. Maybe you are having some sort of sound issue, and can not hear these? Can you reproduce this issue with an Ubuntu LIVE CD and report back if the problem still exists on Ubuntu 8.10 LIVE CD?

We are closing this bug report because it lacks the information we need to investigate the problem, as described in the previous comments. Please reopen it if you can give us the missing information, and don\'t hesitate to submit bug reports in the future. To reopen the bug report you can click on the current status, under the Status column, and change the Status back to New. Thanks again!.

Solved. see below.

The problem involved having TWO sound cards, one on the motherboard and a PCI. Although the PCI card was set as default, apparently system sounds were designed to default to the motherboard card if available. the conflict between the cards was, apparently, shutting down both.
I discovered the solution to the problem in the answer to another question, where it was suggested blacklisting the motherboard card was the only way to shut it down completely. I did that, with immediate favourable results!
I apologise for not posting the solution. I realize it could be of help to others!

This bug report is being closed due to your last comment regarding this being fixed with an update. For future reference you can manage the status of your own bugs by clicking on the current status in the yellow line and then choosing a new status in the revealed drop down box. You can learn more about bug statuses at https://wiki.ubuntu.com/Bugs/Status . Thank you again for taking the time to report this bug and helping to make Ubuntu better. Please submit any future bugs you may find.