December 9, 2014
Volume 6 (Region One) released on October 21, 2008.Season 6 (Region Two) released on October 15, 2007.It should be noted that the "Season 6" DVD does not actually contain episodes from Season 6. It is simply Season 6 in name only.
Perhaps it's the region code on the DVD.
If you have a multi region DVD player you can buy this DVD from amazon.com for $19.99.
Season 11 set released onJune 9th 2014 for Region Two.May 14th 2014 for Region Four.-This set was released for Region One on December 17th 2013 & was called Volume 12
October 1, 2009
November 10th, 2008
In Region One, Season 5 was released December 6th, 2011
Region One | March 10, 2009 Region Two | May 24, 2009
Region One | September 17, 2013 Region Two | October 28, 2013
Region One | May 02, 2006Region Two | No release plannedRegion Four | No release planned
Region 2: A release date has yet to be determined
November 2, 2009It should be noted that the "Season 8" DVD does not actually contain episodes from Season 8. It is simply Season 8 in name only.