based on infromation from
http://www.squid-cache.org/mail-archive/squid-users/200304/0003.html

--- squid-2.5.STABLE12/configure.in~	2005-10-31 17:27:14.000000000 +0200
+++ squid-2.5.STABLE12/configure.in	2005-10-31 17:47:07.000000000 +0200
@@ -1242,6 +1242,13 @@
 	;;
 esac
 
+AC_ARG_WITH(auth-on-acceleration,
+[  --with-auth-on-acceleration      Enable authentication on accelerated request.],
+[ if test "$withval" = yes; then
+	AC_DEFINE([AUTH_ON_ACCELERATION], [1], [Enable authentication on accelerated request.])
+  fi
+])
+
 dnl Check for programs
 AC_PROG_CPP
 AC_PROG_INSTALL