diff -ru a/trunk/Makefile b/trunk/Makefile
--- a/trunk/Makefile	2009-11-22 23:48:23.354960228 +0200
+++ b/trunk/Makefile	2009-11-22 23:57:59.552962626 +0200
@@ -155,6 +155,10 @@
 DEBUG_CFLAGS=-g -O0
 endif
 
+ifndef CUSTOM_OPTIMIZE
+CUSTOM_OPTIMIZE=0
+endif
+
 #############################################################################
 
 BD=$(BUILD_DIR)/debug-$(PLATFORM)-$(ARCH)
@@ -909,6 +913,12 @@
   STRIP_FLAG = -s
 endif
 
+ifeq ($(CUSTOM_OPTIMIZE),1)
+  # User has own optimization flags in CFLAGS
+  OPTIMIZE := $(filter -D%,$(OPTIMIZE))
+  OPTIMIZEVM := $(filter -D%,$(OPTIMIZEVM))
+endif
+
 BASE_CFLAGS += -DPRODUCT_VERSION=\\\"$(VERSION)\\\"
 
 ifeq ($(V),1)