MinecraftForge/MinecraftForge — pull request #1248 by Azaka7 (2014-07-24 23:39:52+00:00)
Title: Pre-Brewing Event

Allows modders to affect the contents of a Brewing Stand when the brewing timer is up in order to
override vanilla brewing. More information and reasoning can be found on a post in the Suggestions section of the Minecraft Forge forums:
http://www.minecraftforge.net/forum/index.php/topic,21637.msg109709.html#msg109709