Don't fail if there's a : in CFLAGS or LDFLAGS.
--- a/Makefile
+++ b/Makefile
@@ -63,8 +63,8 @@ make.fil: $(IFDEFNAME) makefile.in
 	echo >> tmp.sed "s:%MANDIR%:$(MANDIR):"
 	echo >> tmp.sed "s:%ELKSSRC%:$(ELKSSRC):"
 	echo >> tmp.sed "s:%CC%:$(CC):"
-	echo >> tmp.sed "s:%CFLAGS%:$(CFLAGS):"
-	echo >> tmp.sed "s:%LDFLAGS%:$(LDFLAGS):"
+	echo >> tmp.sed "s|%CFLAGS%|$(CFLAGS)|"
+	echo >> tmp.sed "s|%LDFLAGS%|$(LDFLAGS)|"
 	sed -f tmp.sed < tmp.mak > make.tmp
 	mv -f make.tmp make.fil
 	@rm -f tmp.mak tmp.sed