Found It! grr... src/acl/Time.h
Your filesystem appears to be case-insensitive.We already worked out what the fix should be since its needed elsewhere for future changes. I'm testing to see what the effect is on current code and will commit ASAP.
Amos -- Please be using Current Stable Squid 2.7.STABLE6 or 3.0.STABLE14 Current Beta Squid 3.1.0.7