On Mon Sep 16 17:37:20 2013, Ben Reser wrote: > This looks like your mod_security configuration doesn't know about > chunked encoding for requests. 1.8.x now prefers to use chunked > encoding in requests. I'm not sure what you need to change to > configure mod_security to allow chunked requests but that's what you'll > probably want to do.
Based on this it looks like you're running an out of date version of mod_security: http://serverfault.com/questions/65733/why-does-modsecurity-require-content-length-in-post-requests
