diff --git a/common/config.mk b/common/config.mk
index 32d8e3e22..421de6c97 100644
--- a/common/config.mk
+++ b/common/config.mk
@@ -16,7 +16,8 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
-INCLUDES += -I../common -I./
+COMMON_INCS = -I../common -I../relay
+INCLUDES += $(COMMON_INCS) -I./
 
 COMMONDIR ?= ../common
 COMMONOBJDIR = ../common/$(PLATFORM)