AC_CHECK_LIB([netfilter_queue], [nfq_set_queue_maxlen],AC_DEFINE_UNQUOTED([HAVE_NFQ_MAXLEN],[1],[Found queue max length support in netfilter_queue]) ,,[-lnfnetlink])
AC_CHECK_LIB([netfilter_queue], [nfq_set_verdict2],AC_DEFINE_UNQUOTED([HAVE_NFQ_SET_VERDICT2],[1],[Found nfq_set_verdict2 function in netfilter_queue]) ,,[-lnfnetlink])
# check if the argument to nfq_get_payload is signed or unsigned
AC_MSG_CHECKING([for signed nfq_get_payload payload argument])