Joining XP to Samba PDC (DNS SRV records issues)

I'm trying to run a Samba 2.2.7 server (RH 7.3) as a PDC for MS Windows XP
Professional client. I've done all the steps named in the manuals:

1.- Configure smb.conf for PDC.
2.- Create UNIX and Samba accounts and passwords for XP users and machines.
3.- Create root Samba account and password.
3.- Configure registry and security policies in WinXP.
4.- Restart Samba. :-)

But, if I tried to set up my first XP client as a member of the domain
(Control Panel -> System -> Computer Name (or something like that, I'm
using spanish menus,s o I don't know the exact translation) -> Change),
only get the following error:

************************************************** *************************
Note: This information is intended for a network administrator. If you are

not your network's administrator, notify the administrator that you
received this information, which has been recorded in the file
C:\WINDOWS\debug\dcdiag.txt.

The domain name main might be a NetBIOS domain name.
If this is the case, verify that the domain name is properly
registered with WINS.

If you are certain that the name is not a NetBIOS domain name, then the
following information can help you troubleshoot your DNS configuration.

The following error occurred when DNS was queried for the service location
(SRV) resource record used to locate a domain controller for domain main:

The error was: "DNS name does not exist." (error code 0x0000232B
RCODE_NAME_ERROR)

The query was for the SRV record for
_ldap._tcp.dc._msdcs.MY_DOMAIN

Common causes of this error include the following:

- The DNS SRV record is not registered in DNS.

- One or more of the following zones do not include delegation to its
child zone:

MY_DOMAIN
. (the root zone)

For information about correcting this problem, click Help.
************************************************** *************************

So, I guess I've to add an DNS SRV record for my internal zone. My DNS
(BIND 9.2.1) is splitted in 2 zones, external (seen from Internet) and
internal (seen from the LAN).

My question is: Has somebody done this (added the SRV record in the DNS)
What is the sintax for this? I've search a lot in Google, but the nearest
to an example that I've found is

http://www.faqs.org/rfcs/rfc2052.html and I really don't understand very
much about the sintax for SRV records.

What would be the correct sintax in my DNS zones for
_ldap._tcp.dc._msdcs.MY_DOMAIN?

Or even better, does anybody knows what is the useful step to get XP added
to Samba PDC?

Thanks a lot for your help

--
Atte.
Álvaro Palma Aste
************************************************** ****
It's the only form of protest they're allowed
I've seen their silent faces scream so loud
If they were to speak these words they'd go missing too
Another woman on a torture table what else can they do

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