The context for this thread is that this support thread is asking for support with a hacked client, and we (the forum staff) have allowed that thread to continue to exist. There was a discussion in a Private Message between myself and Herb_ regarding whether or not we permit hacked clients, and here is an excerpt that clarifies my position:
"My understanding of "hacked" vs. "cracked" clients is that a "hacked" client is a non-Mojang client that may have additional features but is one that obeys the Minecraft session system, meaning only[/b] those with a copy of Minecraft can play the game. A "cracked" client is one that does not respect the Minecraft session system and allows anyone with the client to play regardless of their ownership of the game -- like offline mode. The forum explicitly does not allow piracy (which includes cracked clients, because cracked clients allow people who don't own Minecraft to play it) but does not disallow "hacked" clients because they aren't piracy, rather they are essentially game modifications."
"Although historically we have attempted to enforce the Mojang EULA on their behalf, it is very difficult because Mojang themselves are inconsistent in their enforcement and there is a lack of clarity surrounding a number of issues. The forum rules require that members abide by the Mojang EULA, but this does not mean that we will attempt to enforce the Mojang EULA as it is written on the behalf of Mojang, this is because we have found it exceptionally difficult to do that with any level of consistency in the past.
Essentially, the Mojang EULA exists as a document Mojang choose to enforce on a case by case basis, therefore when we require members abide by the Mojang EULA we are requiring they abide by Mojang enforcement. This means in practice if Mojang makes a judgement against something (e.g: they say "launcher x is banned") then we would enforce that by removing the launcher from the forum, however, if the launcher exists in a grey area and Mojang have never passed judgement on it, we would not take any action. This extends to the discussion of such launchers too: unless Mojang explicitly states that they wish to ban all custom launchers, we will permit discussion."
As it stands, the official forum position is that cracked clients are [b]not[/b] permitted (no support, no discussion, no distribution) and hacked clients [b]are[/b] permitted (support, discussion, distribution). This is based on my understanding of hacked vs. cracked, if my understanding is wrong then I am open to reviewing the forum rules.