Fix configuration file search path

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>

Changelog

@@ -1,12 +1,13 @@
 Stable versions
 ---------------
 
-4.0.3 (20130420):
+4.0.3 (20130421):
 	- Fix native-endian coreaudio output (reported by Misty De Meo)
 	- Fix MinGW32 build (reported by vaseleos0)
 	- Fix Cygwin build (reported by Benjamin Shadwick)
-	- Fix module-specifc flag settings to override build-in quirks
-          (requires libxmp 4.1 or later)
+	- Fix module-specifc flags to override built-in quirks (requires
+	  libxmp 4.1 or later)
+	- Don't place configuration file in places like /usr/local/etc
 
 	New features requested by Benjamin Shadwick:
 	- Add commands '<' and '>' to jump to previous/next sequence

configure.ac

@@ -20,6 +20,20 @@ if test "$libxmp_path" != ""; then
   LIBS="${LIBS} -L${libxmp_path}/lib"
 fi
 
+dnl Don't use things like /usr/etc or /usr/var
+
+fix_prefix=no
+if test "x$prefix" = xNONE; then
+    fix_prefix=yes
+elif test "x$prefix" = x/usr -o "x$prefix" = x/usr/local; then
+    fix_prefix=yes
+fi
+
+if test $fix_prefix = yes -a $sysconfdir = '${prefix}/etc'; then
+    sysconfdir=/etc
+    localstatedir=/var
+fi
+
 AC_DEFUN([AC_CHECK_DEFINED],[
   AS_VAR_PUSHDEF([ac_var],[ac_cv_defined_$1])dnl
   AC_CACHE_CHECK([for $1 defined], ac_var,