What I expected to happen was...:
I Chat something and it appears
What actually happened was...:
I type something in and it crashed minecraft!
Environment
OS: Windows 7 (ver 6.1, arch amd64)
Java: 1.6.0_17 (by Sun Microsystems Inc.)
Launcher: 1.1.3 (bootstrap 5)
Minecraft: 1.6.2 (updated Tue Jul 09 13:59:42 CDT 2013)
Based on a crash report provided in this issue, I believe with high certainty that this report may be a duplicate of MC-20163. You can view all information known about this specific crash at MCX-878.