[squid-users] About reply_body_max_size

Reading squid.conf.documented for 3.1.9, I see this portion:

TAG: reply_body_max_size size [acl acl...]
# This option specifies the maximum size of a reply body. It can be
# used to prevent users from downloading very large files, such as
# MP3's and movies. When the reply headers are received, the
# reply_body_max_size lines are processed, and the first line where
# all (if any) listed ACLs are true is used as the maximum body size
# for this reply.
#
# This size is checked twice. First when we get the reply headers,
# we check the content-length value. If the content length value exists
# and is larger than the allowed size, the request is denied and the
# user receives an error message that says "the request or reply
# is too large." If there is no content-length, and the reply
# size exceeds this limit, the client's connection is just closed
# and they will receive a partial reply.
#
# WARNING: downstream caches probably can not detect a partial reply
# if there is no content-length header, so they will cache
# partial responses and give them out as hits. You should NOT
# use this option if you have downstream caches.
#
# WARNING: A maximum size smaller than the size of squid's error
messages
# will cause an infinite loop and crash squid. Ensure that the smallest
# non-zero value you use is greater that the maximum header size plus
# the size of your largest error page.
#
# If you set this parameter none (the default), there will be
# no limit imposed.
#
# Configuration Format is:
# reply_body_max_size SIZE UNITS [acl ...]
# ie.
# reply_body_max_size 10 MB

Now, having the following line causes squid (3.1.9) to grok:

reply_body_max_size 0 KB deny all

squid -k parse gives this:

2011/06/05 21:03:05| aclParseAclList: ACL name 'KB' not found.
FATAL: Bungled squid.conf line 60: reply_body_max_size 0 KB deny all
Squid Cache (Version 3.1.9): Terminated abnormally.
CPU Usage: 0.007 seconds = 0.007 user + 0.000 sys
Maximum Resident Size: 4376 KB
Page faults with physical i/o: 0

Where is the problem?

-- 
Best regards,
Odhiambo WASHINGTON,
Nairobi,KE