Lost Season 3: Limited Edition?

[BigDumbWookiee]

Was the release for Lost: Season 3 that included the hard cardboard flap case with the letter from the producers a limited edition or exclusive release? I recently purchased the set on eBay, and to my surprise the cardboard case wasn't included, only the standard plastic one. When I emailed the seller, he told me it wasn't included when he got it. I called Buena Vista Home Entertainment customer service, and they had no record of it in their inventory for replacement. I see plenty of both versions (with and without the cardboard case) on eBay, but don't get why some do and some don't include it.