As I understand it, you tried to remove lava by placing a log down and the game crashed. In that case, this is part of a bug that crashes the game when a log is placed (regardless of other block's involvement) and thus a duplicate of MC-56893, which has already been fixed for the next snapshot (presumably 14w25b).
Oops. Is there a way I can delete this post or flag it as a duplicate? There doesn't seem to be such an option. Thanks for noticing that, by the way. I searched earlier and didn't come up with anything, it seems I was too specific >.<.
Lord Penguin
As I understand it, you tried to remove lava by placing a log down and the game crashed. In that case, this is part of a bug that crashes the game when a log is placed (regardless of other block's involvement) and thus a duplicate of MC-56893, which has already been fixed for the next snapshot (presumably 14w25b).