diff --git a/pkgs/tools/networking/fdm/default.nix b/pkgs/tools/networking/fdm/default.nix
index 0f563cb892af..052367400efc 100644
--- a/pkgs/tools/networking/fdm/default.nix
+++ b/pkgs/tools/networking/fdm/default.nix
@@ -33,7 +33,7 @@ rec {
     sed -i */Makefile -i Makefile -e 's@ -o root @ @'
     sed -i GNUmakefile -e 's@ -g $(BIN_OWNER) @ @'
     sed -i GNUmakefile -e 's@ -o $(BIN_GROUP) @ @'
-    sed -i */Makefile -i Makefile -e 's@-I-@@g'
+    sed -i */Makefile -i Makefile -i GNUmakefile -e 's@-I-@@g'
   '') ["minInit" "doUnpack"];
       
   meta = {