Strange misses...

As I went looking for Communicator refresh problems, I found the
following:

870096453.812 1476 130.211.100.59 TCP_MISS/200 8927 GET
http://www.msnbc.com/news/global/freeie.gif - DIRECT/www.msnbc.com image/gif
870096853.371 1735 130.211.100.96 TCP_MISS/304 29 GET
        http://www.msnbc.com/news/global/freeie.gif - DIRECT/www.msnbc.com -
870096886.050 11935 130.211.100.96 TCP_MISS/304 29 GET
        http://www.msnbc.com/news/global/freeie.gif - DIRECT/www.msnbc.com -
870096894.817 4074 130.211.100.96 TCP_MISS/304 29 GET
        http://www.msnbc.com/news/global/freeie.gif - DIRECT/www.msnbc.com -
870096924.287 1354 130.211.100.96 TCP_MISS/304 29 GET
        http://www.msnbc.com/news/global/freeie.gif - DIRECT/www.msnbc.com -

Any idea why this might be happening? Why isn't their browser using their
local disk cache for this image, and why isn't the cache returning a hit
for it? As you can see, these accesses are all within a fairly short span
of one another, and I have a refresh_pattern line for GIF files:

refresh_pattern/i ^http://.*\.gif$ 10080 90% 40320

        -Mike Pelletier.
Received on Mon Jul 28 1997 - 12:00:08 MDT