World has gone upgrades as follows:
1.7
1.8
1.8.1-pre1
1.8.1-pre2
Any higher than this (pre3 / pre4) though all nether portals start acting oddly. Players transport through the portal however end up appearing either in the overworld or the nether 2-3 blocks to the side of where the portal actually is.
This has resulted in smothering in walls, falling to death in lava, and other horrible deaths.
Related issues
Comments

duplicate of MC-73504 Mods please merge.