Trying to compile squid-2.5.PRE10 under Jagwire but didn't get very far when "making":
util.c:79: conflicting types for `sys_nerr'
/usr/include/stdio.h:265: previous declaration of `sys_nerr'
make[1]: *** [util.o] Error 1
make: *** [all-recursive] Error 1
Making the latest squid-2.4 tarball also ended with the same error. Probably has something to do with Apple moving the libs around a bit, but I've no clue how to work around it.
PS: squid-2.5.PRE10 built under OS X 10.1.5 continues to function fine
under 10.2.