diskless netmask problem

[alexs at analytic.mv.ru]

Setup diskless in ip/22 subnet

dhcpd.conf
subnet 192.168.0.0 netmask 255.255.252.0 {
  use-host-decl-names on;
  option subnet-mask 255.255.252.0;
  option broadcast-address 192.168.3.255;

  host bart {
    hardware ethernet 00:1c:c0:85:48:fe;
    fixed-address 192.168.0.72;
    filename "pxeboot";
    option root-path "192.168.0.160:/export/diskless/freebsd71";
  }
}

System starts ok, but netmask on interface is not 255.255.252.0,
it gets 255.255.255.0

if put nfs server in 192.168.1.0-192.168.3.255, i have nfs_mountroot error.

-- 
alexs