--- Makefile.in.orig	Thu May 11 17:38:28 2006
+++ Makefile.in	Thu May 11 17:38:51 2006
@@ -23,7 +23,8 @@
 src_dir = .
 
 CC = @CC@
-CFLAGS = -Wall -O2  \
+CPPFLAGS = @CPPFLAGS@
+CFLAGS = -Wall -O2 $(CPPFLAGS) \
          -DCONFIG_FILE=\"$(config_dir)/arpalert.conf\" \
          -DPID_FILE=\"$(lock_dir)/arpalert.pid\"
 LIBS = @LIBS@