diff --git a/Kernel/Makefile b/Kernel/Makefile
index bb76c1310f56dac0cf3925dde76e411920a7ddc6..0b79233b3a5584bc1db6a083cf17fdf8bbf5066f 100644
--- a/Kernel/Makefile
+++ b/Kernel/Makefile
@@ -10,8 +10,8 @@
 
 -include Makefile.BuildNum.$(ARCH)
 
-ifeq ($(BUILDNUM),)
-BUILDNUM = 0
+ifeq ($(BUILD_NUM),)
+BUILD_NUM = 0
 endif
 
 KERNEL_VERSION = 0.5