I was playing on a friend's server in snapshot 12w25a, and after he had to take down the server, I decided to try and find some cool seeds.

I tried seed "ihaveabsolutelynoidea", which spawned me in a taiga biome. After I spawned, I notice a chunkfail. "bleh, invisible chunks, been there seen that", I think, so I fly up a bit and over the chunkfail. To my suprise the lighting fails to work inside it. I got back on the area that proved to be only 5 chunks big and dug a bit and hit a ravine. I then noticed the mobs. They were frozen. I dug a bit more and saw that the thin sheets of snow weren't breaking. I then tried some more stuff and saw that block updating didn't work. Then, I saw I couldn't even discard the items in my inventory. Cool seed, broken world. I closed and restarted the world, and it worked normally.

I then tried seed "ogmloel", which spawned me in a small chunk o' desert at the edge of a taiga biome.  Proves that this world was also 5 chunks big. I made a small radio tower thingie out of wool and then tried to restart the world. This time, to my surprise, it didn't work, the world was still 5 chunks big and frozen. I flew a bit and found a ravine under this one as well.

Last world, I didn't put a seed in. The world generated normally, and I flew for a while, but then I realised that the mobs were frozen here too, and block updates didn't work. I then saw this world also ends abruptly, just a bit further. I then saw some chunkfail around.

Thing is, some of my friends tried generating a world with the same seeds in the snapshot and had no problem.

Halp?

@vanquish349 (View Post)

 but it only happens for me, my friends aren't getting worlds generated this way