--- nvidia-drivers-173.14.09.ebuild	2008-06-17 23:40:05.000000000 +0200
+++ nvidia-drivers-173.14.09-r1.ebuild	2008-06-30 23:54:38.000000000 +0200
@@ -216,7 +216,9 @@
 			"${NV_SRC}"/Makefile.kbuild
 
 		# If you set this then it's your own fault when stuff breaks :)
-		use custom-cflags && sed -i "s:-O:${CFLAGS}:" Makefile.*
+		use custom-cflags \
+		    && einfo "Patching ${NV_SRC}/Makefile* to respect custom cflags" \
+		    && sed -i "s:-O:${CFLAGS}:" "${NV_SRC}"/Makefile.*
 
 		# If greater than 2.6.5 use M= instead of SUBDIR=
 		convert_to_m "${NV_SRC}"/Makefile.kbuild