diff --git a/recipes/doxymacs.rcp b/recipes/doxymacs.rcp
index 1c985ed5..22029a1f 100644
--- a/recipes/doxymacs.rcp
+++ b/recipes/doxymacs.rcp
@@ -5,8 +5,8 @@
        :url "git://doxymacs.git.sourceforge.net/gitroot/doxymacs/doxymacs"
        :load-path ("./lisp")
        :build ("./bootstrap" "./configure" "make")
-       :build/darwin ("sed -i -e 's/-fexpensive-optimizations//' ./c/Makefile.am"
-                      "sed -i -e 's/inline/static inline/' ./c/doxymacs_parser.c"
+       :build/darwin ("sed -i '' -e 's/-fexpensive-optimizations//' ./c/Makefile.am"
+                      "sed -i '' -e 's/inline/static inline/' ./c/doxymacs_parser.c"
                       "./bootstrap" "./configure" "make")
        :prepare (progn
                   (autoload 'doxymacs-mode "doxymacs" nil t)))