help explain a directive

["J. Peng" <peng.kyo@xxxxxxxxx>]

from squid.conf.default (for squid-2.7):

#  TAG: server_http11   on|off
#       This option enables the use ot HTTP/1.1 on outgoing "direct" requests.
#       See also the http11 cache_peer option.
#       Note: The HTTP/1.1 support is still incomplete.
#
#Default:
# server_http11 off



what's the usage of this directive?
Shall I use it on http1.1 proxy?

Thanks!