[squid-users] why RELEASE?

I am using Squid 3.0.STABLE10 and seeing something strange.

I recently increased the filesystem that my cache is on by about 5x.
It's now showing:

Filesystem Size Used Avail Use% Mounted on
/dev/mapper/rootvol-http_cache
                      9.9G 1.6G 7.8G 17% /var/spool/squid3

I also updated my squid.conf's cache_dir setting to reflect the new
space, and yet I am seeing things being purged from disk that I don't
think should be, such as:

1238571305.439 RELEASE 00 00012854 00F9A61E772676B12CBC5AE555118AA7 200 1238570702 1234617781 -1 image/gif 156/156 GET http://www.xyz.org/forum/images/styles/footer_bg.gif

Why would such a static object be removed from the cache when there is
so much space available.

The cachemgr reports Swap stats as:

        Storage Swap size: 1568292 KB
        Storage Swap capacity: 19.1% used, 80.9% free

So it seems that squid does see the new space available too.

Thots?

b.