According to Aniplex, a 10min short anime of Gintama "Shiroyasha Koutan" will be released on September 30th. It was shown at Jump Super Anime Tour 2008 and had never been released as a DVD.
It's a trailer of an imaginary Gintama movie. Gintama OVA shown at Jump Anime Tour '05 is also included in the DVD.+ More
Characters & Voice Actors

Kagura
Main
Elizabeth
Supporting
Hasegawa, Taizou
Supporting
Hijikata, Toushirou
Supporting
Katsura, Kotarou
Supporting
Kondou, Isao
Supporting
Okita, Sougo
Supporting
Sakamoto, Tatsuma
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