--- a/configure.in
+++ b/configure.in
@@ -3423,17 +3423,17 @@ dnl = If NSS was not detected in the sys
 dnl = use the one in the source tree (mozilla/security/nss)
 dnl ========================================================
 
 MOZ_ARG_WITH_BOOL(system-nss,
 [  --with-system-nss       Use system installed NSS],
     _USE_SYSTEM_NSS=1 )
 
 if test -n "$_USE_SYSTEM_NSS"; then
-    AM_PATH_NSS(3.20.1, [MOZ_NATIVE_NSS=1], [AC_MSG_ERROR([you don't have NSS installed or your version is too old])])
+    AM_PATH_NSS(3.21, [MOZ_NATIVE_NSS=1], [AC_MSG_ERROR([you don't have NSS installed or your version is too old])])
 fi
 
 if test -n "$MOZ_NATIVE_NSS"; then
    NSS_LIBS="$NSS_LIBS -lcrmf"
 else
    NSS_CFLAGS='-I$(LIBXUL_DIST)/include/nss'
 
    if test -z "$GNU_CC" -a "$OS_ARCH" = "WINNT"; then