samba - Sep 2003 - Failed to join Domain with samba 3rc4

I am trying to join join a windows 2000 domain with samba 3rc4.

When I use : net rpc join -S SERVDOM -w DOMNAME -U Administrator%passwd

I got the following error message
/*
[2003/09/15 12:11:30, 0] utils/net_rpc_join.c:net_rpc_join_newstyle(286)
  error setting trust account password: NT_STATUS_WRONG_PASSWORD
Unable to join domain MONDOM.
*/

When I test "smbpasswd -r SERVDOM -j MONDOM -U Administrator%passwd"
on another machine with samba 2.2 it goes well and I got the
following message : /* Joined domain MONDOM */

Have you some idea.

Thanks

Thomas