Index: trunk/zoo-project/zoo-kernel/Makefile.in
===================================================================
--- trunk/zoo-project/zoo-kernel/Makefile.in	(revision 951)
+++ trunk/zoo-project/zoo-kernel/Makefile.in	(revision 952)
@@ -42,5 +42,5 @@
 
 service_json.o: service_json.c
-	g++ -fPIC ${JSON_CFLAGS} ${CFLAGS} -c service_json.c
+	g++ -fPIC ${XML2CFLAGS} ${JSON_CFLAGS} ${CFLAGS} -c service_json.c
 
 service_callback.o: service_callback.c
Index: trunk/zoo-project/zoo-kernel/configure.ac
===================================================================
--- trunk/zoo-project/zoo-kernel/configure.ac	(revision 951)
+++ trunk/zoo-project/zoo-kernel/configure.ac	(revision 952)
@@ -74,5 +74,5 @@
 if test "x$JSON_DIR" != "x" && test "x$CALLBACK_ACTIVATED" == "xyes"
 then
-	JSON_CPPFLAGS="-I$JSON_DIR/include/json-c/"
+	JSON_CPPFLAGS="-DUSE_JSON -I$JSON_DIR/include/json-c/"
 	JSON_LDFLAGS="-L$JSON_DIR/lib -ljson-c"
 	CPPFLAGS_SAVE="$CPPFLAGS"
@@ -87,6 +87,9 @@
 	JSON_FILE="service_json.o"
 	JSON_ENABLED="-DJSON"
-	CALLBACK_FILE="service_callback.o"
-	CALLBACK_USE="-DUSE_CALLBACK"
+	if test "x$CALLBACK_ACTIVATED" == "xyes"
+	then
+		CALLBACK_FILE="service_callback.o"
+		CALLBACK_USE="-DUSE_CALLBACK"
+	fi
 fi
 AC_SUBST([JSON_CPPFLAGS])