Logging into a specific SMP server causes MC to crash

I was placing lava under glass panes, under ice, and when the lava flowed and contacted my player, my Minecraft crashed. The multiplayer server I was playing on, also crashed. When the server came back on, I tried connecting again, but when I do, it only connects for a split second and my game crashes again. But the server still stays up. I can connect with no problem to other servers.

I've attached the first and last crash reports I got from the game when this occured.