trouble with filter

["Giulio Federici" <giulio.federici@gmail.com>]

hi, i have a openldap 2.2.23 (official package 2.2.23-8 on debian stable):

test:~# slapcat
dn: dc=burp
objectClass: top
objectClass: dcObject
objectClass: organization
o: burp
dc: burp
structuralObjectClass: organization

dn: cn=admin,dc=burp
objectClass: simpleSecurityObject
objectClass: organizationalRole
cn: admin
description: LDAP administrator
userPassword:: <xxx>

dn: ou=People,dc=burp
objectClass: top
objectClass: organizationalUnit
ou: People
structuralObjectClass: organizationalUnit

dn: ou=Media,dc=burp
objectClass: top
objectClass: organizationalUnit
ou: Media
structuralObjectClass: organizationalUnit

test:~# cat /etc/ldap/slapd.conf 
include         /etc/ldap/schema/core.schema
include         /etc/ldap/schema/cosine.schema
include         /etc/ldap/schema/nis.schema
include         /etc/ldap/schema/inetorgperson.schema

schemacheck     on

pidfile         /var/run/slapd/slapd.pid

argsfile        /var/run/slapd.args

loglevel        0

modulepath    /usr/lib/ldap
moduleload    back_bdb

backend        bdb
checkpoint 512 30

database        bdb

suffix          "dc=burp"

directory       "/var/lib/ldap"

index           objectClass eq

lastmod         on

access to attrs=userPassword
        by dn="cn=admin,dc=burp" write
        by anonymous auth
        by self write
        by * none

access to dn.base="" by * read

access to *
        by dn="cn=admin,dc=burp" write
        by * read


test:~# ldapsearch -x -D "cn=admin,dc=burp" -w <xxx> -s sub -b "dc=burp" "(objectClass=*o*)"
# extended LDIF
#
# LDAPv3
# base <dc=burp> with scope sub
# filter: (objectClass=*o*)
# requesting: ALL
#

# search result
search: 2
result: 0 Success

# numResponses: 1
test:~#


test:~# slapd -d 6
@(#) $OpenLDAP: slapd 2.2.23 (May 30 2005 08:52:42) $
    @pulsar:/home/torsten/packages/openldap/openldap2.2-2.2.23/debian/build/servers/slapd
daemon_init: <null>
bdb_db_init: Initializing BDB database
bdb_db_open: dc=burp
slapd starting
connection_get(10)
ldap_read: want=8, got=8
  0000:  30 24 02 01 01 60 1f
02                           
0$...`..          
ldap_read: want=30, got=30
  0000:  01 03 04 10 63 6e 3d 61  64 6d 69 6e 2c 64 63 3d   ....cn=admin,dc=  
  0010:  62 75 72 70 80 08 34 38  37 72 61 73 69
6d         burp..<xxx>
ldap_read: want=8 error=Resource temporarily unavailable
==> bdb_bind: dn: cn=admin,dc=burp
send_ldap_result: err=0 matched="" text=""
  0000:  30 0c 02 01 01 61 07 0a  01 00 04 00 04
00        
0....a........    
ldap_write: want=14, written=14
  0000:  30 0c 02 01 01 61 07 0a  01 00 04 00 04
00        
0....a........    
connection_get(10)
ldap_read: want=8, got=8
  0000:  30 33 02 01 02 63 2e
04                           
03...c..          
ldap_read: want=45, got=45
  0000:  07 64 63 3d 62 75 72 70  0a 01 02 0a 01 00 02 01   .dc=burp........  
  0010:  00 02 01 00 01 01 00 a4  12 04 0b 6f 62 6a 65 63   ...........objec  
  0020:  74 43 6c 61 73 73 30 03  81 01 6f 30
00           
tClass0...o0.     
ldap_read: want=8 error=Resource temporarily unavailable
SRCH "dc=burp" 2 0    0 0 0
    filter: (?=undefined)
    attrs:
bdb_idl_fetch_key: [b49d1940]
send_ldap_result: err=0 matched="" text=""
  0000:  30 0c 02 01 02 65 07 0a  01 00 04 00 04
00        
0....e........    
connection_get(10)
ldap_write: want=14, written=14
  0000:  30 0c 02 01 02 65 07 0a  01 00 04 00 04
00        
0....e........    
ldap_read: want=8, got=7
  0000:  30 05 02 01 03 42
00                              
0....B.           
ldap_read: want=8, got=0

slapd shutdown: waiting for 0 threads to terminate
slapd stopped.
test:~#

any idea?