SOLVED. See below.
On Sat, 27 Aug 2011 11:15:00 -0600
Mario Guerra <mguerra(a)nic.cr> wrote:
  Hello:
 I'm informing that we, as of August 26th., have implemented FRED completely, as a
backend for our DNS administration.
 I have a question, though about a domain, corobicicp.co.cr. Let's see first the FRED
information:
 NIC-REG1(a)127.0.0.1> info_domain corobicicp.co.cr
 Domain name:              corobicicp.co.cr
 Repository object ID:     D0000030043-EPP
 Created by:               NIC-REG1
 Designated registrar:     NIC-REG1
 Created on:               2007-10-10T18:00:00-06:00
 Expiration date:          2011-10-10 <------- it has not expired
 NSSET ID:                 COROBICICP_CO_CR <-------------------
 Password for transfer:    bfjZP1C6
 Status:                   ok - Objekt is without restrictions
 Registrant ID:            CESAR.SALAS_AT_COROBICICP.CO.CR
 Administrative contact:   CESAR.SALAS_AT_COROBICICP.CO.CR
 NIC-REG1(a)127.0.0.1> info_nsset COROBICICP_CO_CR
 NSSET ID:                 COROBICICP_CO_CR
 Repository object ID:     N0000017473-EPP
 Created by:               NIC-REG1
 Designated registrar:     NIC-REG1
 Created on:               2011-06-03T12:38:40-06:00
 Password for transfer:    CdrNZl0g
 Status:                   linked - Has relation to other records in registry
 Technical contact:        NATALIA.ALVARADO_AT_COROBICICP.CO.CR
 Name servers:             corobicicp.co.cr, (200.122.149.206) <---------------------
                           secundario.nic.cr, (75.125.255.162) <---------------------
 Report level:             3
 Now let see what the corresponding zone files generate:
 root@fred:/tmp# grep corobicicp db*
 db..co.cr:corobicicp.co.cr.    IN      NS      corobicicp.co.cr.
 db..co.cr:corobicicp.co.cr.    IN      NS      secundario.nic.cr.
 As you can see, no A record for the corobicicp.co.cr domain is generated in despite it is
included in the nsset associated with the domain. I'm, though, including what thois
client's DNS server gives us:
 root@fred:/tmp# dig +norec corobicicp.co.cr ns @200.122.149.206
 ; <<>> DiG 9.7.0-P1 <<>> +norec corobicicp.co.cr ns
@200.122.149.206
 ;; global options: +cmd
 ;; Got answer:
 ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41890
 ;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
 ;; QUESTION SECTION:
 ;corobicicp.co.cr.             IN      NS
 ;; ANSWER SECTION:
 corobicicp.co.cr.      3600    IN      NS      dns.corobicicp.co.cr. <-------------
 ;; ADDITIONAL SECTION:
 dns.corobicicp.co.cr.  3600    IN      A       200.122.149.206
 I wonder if this inconssitency have a role for what is generated by genzone_client.
 Best regards.
 --
 Mario Guerra <mguerra(a)nic.cr> 
Well, there is a possible bug in genzone_client or such. If you have a server name which
is the same that the domain (say, both are guerra.co.cr). The name is generated BUT NOT
the correponding A record. In the above case corobicipc.co.cr does NOT generate an A
record, but if I include dns.corobicicp.co.cr with the same A record, both are generated
in the DNS tables.
Best regards.
--
Mario Guerra <mguerra(a)nic.cr>