For gamers Down Under, the pre-loading period for Borderlands was giving them an "incorrect version" to download. It's been replaced now, and so 2K asks you delete and re-download.
"We'd like to confirm that the Australian version of Borderlands is not censored in any way. This applies to all platforms and distribution methods, including Steam," said publisher 2K.
"Because of an internal mix-up an incorrect version of the game was available to preload on Steam for a brief period of time. This version has since been replaced."
"We're asking everybody who has downloaded the Australian version of Borderlands previously to delete the local content and re-download the game to ensure that they have the proper files. We apologise for any inconvenience this may have caused."
Mistakes like this are not uncommon for Steam, like the Merchants of Brooklyn was accidentally released over the digital platform as the alpha build of the game - whoops.