Index: etc/rc.d/jail
===================================================================
--- etc/rc.d/jail	(revision 268273)
+++ etc/rc.d/jail	(working copy)
@@ -647,7 +647,9 @@ jail_start()
 		done
 
 		eval ${_setfib} jail -n ${_jail} ${_flags} -i -c path=${_rootdir} host.hostname=${_hostname} \
-			ip4.addr=\"${_addrl}\" ip6.addr=\"${_addr6l}\" ${_parameters} command=${_exec_start} > ${_tmp_jail} 2>&1
+			${_addrl:+ip4.addr=\"${_addrl}\"} ${_addr6l:+ip6.addr=\"${_addr6l}\"} \
+			${_parameters} command=${_exec_start} > ${_tmp_jail} 2>&1 \
+			</dev/null
 
 		if [ "$?" -eq 0 ] ; then
 			_jail_id=$(head -1 ${_tmp_jail})
