jk_ajp13.h uses (line 43): AJP13_MAX_SEND_BODY_SZ = DEF_BUFFER_SZ - 6 but the start of the message is 2 header bytes 2 bytes for the message length 1 byte for the message type 2 bytes for the chunk length. = a total of 7 bytes. The buffer usable space should be DEF_BUFFER_SZ - 7, if I'm not wrong
Request Body messages don't have a 'type' field in the AJP/1.3 protocol.