Using latest dev build of 0.8.1c, crash seems to be an endless loop of dropBlock

Crash Report - https://gist.github.com/Tencao/12623793e117643b93d3a06ae567726a

Steps to reproduce? Dedicated server or client mode? Which sapling specifically is causing the problem? I'm unable to get it to crash like this.

Dedicated but this may have actually being a world issue. Since starting a new world this hasn't surfaced again, however I shall keep an eye on this and report back if the issue returns.