diff --git a/configure.in b/configure.in
index ff7a23963..f91fe30dd 100644
--- a/configure.in
+++ b/configure.in
@@ -177,7 +177,7 @@ fi
 if test "$with_snmp" = "yes"; then
 	LIBS="$LIBS $SNMP_LIBS"
 	CFLAGS="$CFLAGS $SNMP_CFLAGS"
-	AC_DEFINE([HAVE_LIBSNMP], [1], [net-snmp library is available])
+	AC_DEFINE(HAVE_LIBSNMP, 1, [Define to 1 if you have the net-snmp library.])
 else
 	AC_MSG_WARN([*** Warning: net-snmp library disabled, autodetecting network scanners will not be supported.])
 fi
diff --git a/include/sane/config.h.in b/include/sane/config.h.in
index 3094fa508..02b7da041 100644
--- a/include/sane/config.h.in
+++ b/include/sane/config.h.in
@@ -162,6 +162,9 @@
 /* Define to 1 if you have the libjpeg library. */
 #undef HAVE_LIBJPEG
 
+/* Define to 1 if you have the net-snmp library. */
+#undef HAVE_LIBSNMP
+
 /* Define to 1 if you have libusb. */
 #undef HAVE_LIBUSB