diff --git a/configure b/configure
index 3a09758..971e7e4 100755
--- a/configure
+++ b/configure
@@ -537,8 +537,8 @@ HASH_COMPILE=""
 HASH_LINK=""
 
 if [ $try_nss = "1" ]; then
-  test_cflags="`pkg-config --cflags nss`"
-  test_link="`pkg-config --libs-only-L nss` -lfreebl3"
+  test_cflags="`pkg-config --cflags nss 2> /dev/null`"
+  test_link="`pkg-config --libs-only-L nss 2> /dev/null` -lfreebl3"
   if test_code 'NSS' 'nss.h hasht.h nsslowhash.h' \
     "$test_cflags" "$test_link" \
     'NSSLOWHASH_Begin(NSSLOWHASH_NewContext(NSSLOW_Init(), HASH_AlgSHA512));'