icpDetectClientClose message in cache.log

Dear All,

I have Squid-1.1.20 running, connected through ICP
to 3 parent caches (also Squid-1.1.20).
In the cache.log there appear a lot of messages like the ones appearing
below:
Any hints of what these messages mean?
(Do they imply that the client abandoned the request before completion
of the download? In this case why icpdetect?
Or there is a protocol incompatibility issue lurking behind?)

(Do I have to consult the FAQ or the manual? In this case, forgive me
for taking your time...)
Thanks,

Evaghelos.

Sample messages
a)

1998/04/21 16:23:54| icpDetectClientClose: FD 43, 255 unexpected bytes
1998/04/21 16:23:54| --> from: 194.30.234.207
1998/04/21 16:23:54| --> data:
GET%20http://www.microsoft.com/library/images/gifs/stories/feature.gif%2
0HTTP/1.0%0d%0aAccept:%20*/*%0d%0aReferer:%20http://www.microsoft.com/ie
40.htm%0d%0aAccept-Language:%20el,en-gb;q=0.5%0d%0aAccept-Encoding:%20gz
ip,%20deflate%0d%0aUser-Agent:%20Mozilla/4.0%20(compatible;%20MSIE%204.0
1;%20Window

b)
1998/04/21 16:23:54| icpDetectClientClose: FD 43, 64 unexpected bytes
1998/04/21 16:23:54| --> from: 194.30.234.207
1998/04/21 16:23:54| --> data:
s%2095)%0d%0aHost:%20www.microsoft.com%0d%0aProxy-Connection:%20Keep-Ali
ve%0d%0a%0d%0a
Received on Tue Apr 21 1998 - 08:06:45 MDT