At least some versions of the Totem gstreamer-based media plugin on Linux report the ability to play video/quicktime. OggHandler seems to detect this as QuickTime, and lists "QuickTime" alongside "Ogg plugin". "QuickTime" is selected by default.
While it seems to work, it's a bit odd. :)
Tested on Ubuntu 7.10 with various gstreamer plugins installed.
Version: unspecified
Severity: enhancement
URL: http://commons.wikimedia.org/wiki/Image:La_Donna_E_Mobile_Rigoletto.ogg