Entry not listed when requesting all entries with ldapsearch

[Yeray Gutiérrez Cedrés <ycedres@gmail.com>]

I've added a new entry with ldapadd like this:

I've got this in a file (myfile.ldif):

dn: mail=someone@example.com,ou=alias,ou=postfix,dc=example,dc=com
cn: Mr Someone
mail: someone@example.com
maildrop: someone@corporative.example.com
sn: Boss
objectClass: CourierMailAlias
objectClass: person
objectClass: top
objectClass: inetOrgPerson


$>ldapadd -D "cn=admin,dc=example,dc=com" -w secret -x -h "localhost"
-f myfile.ldif


I can see it if I search specifically for it with ldapsearch (no
problem with this):

$> ldapsearch -x  -b
"mail=someone@example.com,ou=alias,ou=postfix,dc=example,dc=com"
# extended LDIF
#
# LDAPv3
# base <mail=someone@example.com,ou=alias,ou=postfix,dc=example,dc=com>
with scope subtree
# filter: (objectclass=*)
# requesting: ALL
#

# someone@example.com, alias, postfix, someone.com
dn: mail=someone@example.com,ou=alias,ou=postfix,dc=someone,dc=com
cn: Mr Someone
mail: someone@example.com
sn: Boss
objectClass: CourierMailAlias
objectClass: person
objectClass: top
objectClass: inetOrgPerson
maildrop: someone@corporative.example.com

# search result
search: 2
result: 0 Success

# numResponses: 2
# numEntries: 1


Howerver, when I try to search for this entry with ldapsearch I can't
see it if I list all the entries:

$> ldapsearch -x  -b "ou=alias,ou=postfix,dc=example,dc=com" | grep "someone"
$>

I have some other entries that were previously there and they are all
listed. It's very extrange that in the complete list the new etnry
doesn't get listed. Any idea?

Regards.