diff --git a/Makefile.include b/Makefile.include
index 66070fd91..8bad9e2e5 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -77,7 +77,7 @@ endif
 
 include $(CONTIKI)/platform/$(TARGET)/Makefile.$(TARGET)
 
-### Setup directory search path for source files
+### Setup directory search path for source and header files
 
 CONTIKI_TARGET_DIRS_CONCAT = ${addprefix $(CONTIKI)/platform/$(TARGET)/, \
                                $(CONTIKI_TARGET_DIRS)}
@@ -90,6 +90,8 @@ SOURCEDIRS = $(PROJECTDIRS) $(CONTIKI_TARGET_DIRS_CONCAT) \
 vpath %.c $(SOURCEDIRS)
 vpath %.S $(SOURCEDIRS)
 
+CFLAGS += ${addprefix -I,$(SOURCEDIRS)}
+
 ### Automatic dependency generation
 
 ifneq ($(MAKECMDGOALS),clean)
diff --git a/cpu/6502/Makefile.6502 b/cpu/6502/Makefile.6502
index 8b276cf06..716db8d32 100644
--- a/cpu/6502/Makefile.6502
+++ b/cpu/6502/Makefile.6502
@@ -30,7 +30,7 @@
 #
 # Author: Oliver Schmidt <ol.sc@web.de>
 #
-# $Id: Makefile.6502,v 1.8 2007/05/13 08:41:32 oliverschmidt Exp $
+# $Id: Makefile.6502,v 1.9 2007/05/19 07:55:35 oliverschmidt Exp $
 #
 
 ifndef CONTIKI
@@ -69,7 +69,7 @@ LD = ld65
 AR = ar65
 
 AFLAGS  = -t $(TARGET)
-CFLAGS += -t $(TARGET) -Or ${addprefix -I,$(SOURCEDIRS)}
+CFLAGS += -t $(TARGET) -Or
 LDFLAGS = -C $(CONTIKI)/platform/$(TARGET)/linker.cfg -m contiki-$(TARGET).map
 AROPTS  = a
 
diff --git a/cpu/msp430/Makefile.msp430 b/cpu/msp430/Makefile.msp430
index ba52bd832..6af349d86 100644
--- a/cpu/msp430/Makefile.msp430
+++ b/cpu/msp430/Makefile.msp430
@@ -1,4 +1,4 @@
-# $Id: Makefile.msp430,v 1.17 2007/05/15 08:09:45 adamdunkels Exp $
+# $Id: Makefile.msp430,v 1.18 2007/05/19 07:56:34 oliverschmidt Exp $
 
 ifdef nodeid
 CFLAGS += -DNODEID=$(nodeid)
@@ -39,11 +39,7 @@ NM       = msp430-nm
 OBJCOPY  = msp430-objcopy
 STRIP    = msp430-strip
 BSL      = msp430-bsl
-CFLAGSNO = -I. -I$(CONTIKI)/core -I$(CONTIKI_CPU) \
-           -I$(CONTIKI)/platform/$(TARGET) \
-           ${addprefix -I,$(APPDIRS)} \
-           -DWITH_ASCII \
-           -Wall -mmcu=$(MCU) -g
+CFLAGSNO = -Wall -mmcu=$(MCU) -g
 CFLAGS  += $(CFLAGSNO) -Os
 LDFLAGS += -mmcu=$(MCU) -Wl,-Map=contiki-$(TARGET).map
 
diff --git a/cpu/native/Makefile.native b/cpu/native/Makefile.native
index 694ae2d46..c495e783c 100644
--- a/cpu/native/Makefile.native
+++ b/cpu/native/Makefile.native
@@ -8,10 +8,7 @@ LD       = gcc
 AS       = as
 OBJCOPY  = objcopy
 STRIP    = strip
-CFLAGSNO = -I. -I$(CONTIKI) -I$(CONTIKI)/core -I$(CONTIKI_CPU) \
-           -I$(CONTIKI)/platform/$(TARGET) \
-           ${addprefix -I,$(APPDIRS)} $(APP_INCLUDES) \
-          -Wall -g -I. -I/usr/local/include
+CFLAGSNO = -Wall -g -I/usr/local/include
 CFLAGS  += $(CFLAGSNO) -O
 LDFLAGS  = -Wl,-Map=contiki-native.map,-export-dynamic
 
diff --git a/cpu/x86/Makefile.x86 b/cpu/x86/Makefile.x86
index 2ba6d9da9..4b8f0263f 100644
--- a/cpu/x86/Makefile.x86
+++ b/cpu/x86/Makefile.x86
@@ -8,11 +8,7 @@ LD       = gcc
 AS       = as
 OBJCOPY  = objcopy
 STRIP    = strip
-CFLAGSNO = -I. -I$(CONTIKI) -I$(CONTIKI)/core -I$(CONTIKI_CPU) \
-           -I$(CONTIKI)/platform/$(TARGET) \
-           ${addprefix -I,$(APPDIRS)} $(APP_INCLUDES) \
-          -DWITH_UIP -DWITH_ASCII \
-          -Wall -g -I. -I/usr/local/include
+CFLAGSNO = -Wall -g -I/usr/local/include
 CFLAGS  += $(CFLAGSNO)
 LDFLAGS  = -Wl,-Map=contiki.map,-export-dynamic
 
diff --git a/platform/cooja/Makefile.cooja b/platform/cooja/Makefile.cooja
index 81d649cca..9d9721615 100644
--- a/platform/cooja/Makefile.cooja
+++ b/platform/cooja/Makefile.cooja
@@ -1,4 +1,4 @@
-# $Id: Makefile.cooja,v 1.16 2007/05/18 13:51:04 fros4943 Exp $
+# $Id: Makefile.cooja,v 1.17 2007/05/19 07:57:59 oliverschmidt Exp $
 
 ## The COOJA Simulator Contiki platform Makefile
 ##
@@ -75,12 +75,7 @@ CONTIKI_SOURCEFILES += $(CONTIKI_TARGET_SOURCEFILES)
 CONTIKI_CPU=$(CONTIKI)/cpu/x86
 
 ### Compiler arguments
-CFLAGSNO = -I. -I$(CONTIKI_CPU) \
-			$(EXTRA_CC_ARGS) \
-           -I$(COOJA) \
-           -I$(CONTIKI)/core \
-          -DWITH_UIP -DWITH_ASCII \
-          -Wall -g -I. -I/usr/local/include
+CFLAGSNO = $(EXTRA_CC_ARGS) -Wall -g -I/usr/local/include
 CFLAGS   = $(CFLAGSNO)
 
 ### Define custom targets