Since alice was updated to 1.2.5 it seems that nether portals are being buggy. Sometimes, when I go through an overworld portal, I find myself teleported to the top of the nether, a sea of bedrock expanding in every direction. My home portal doesnt work, and neither does that any of my neighbors. The only way for me to get down is to call a mod over to teleport me. I don't like having to do that and neither do the mods, but I don't want to have to walk 3000+ blocks to get to the spawn. My nether portal has worked before and I can think of no reason why it should malfunction like this other that a bug. This seems to be happening to other people also, so I thought that I should bring it to the attention of the community.
hmmm it hasn't happened to me but the only reason that something like that would happen is if your portal is severely screwed up I would suggest destroying it and making a new portal somewhere else.