diff --git a/Makefile.in b/Makefile.in
index 877c54f..3e39ed1 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -209,6 +209,8 @@ $(NSS_VERSION).tar.gz:
 
 $(nss_static_libs): $(NSS_VERSION).tar.gz
 	tar xf $(NSS_VERSION).tar.gz
+	sed -i -e "1s@#!/usr/bin/env bash@#!$$(type -p bash)@" $(NSS_VERSION)/nss/build.sh
+	sed -i -e "s@/usr/bin/env grep@$$(type -p grep)@" $(NSS_VERSION)/nss/coreconf/config.gypi
 
 ifeq ($(host),$(build))
 	# Native build, use NSS' build script.