When do ldapdelete with back-sql. SLAPD core dumped.

[ZhangPu <zhang@fjh.fujitsu.com>]

Hello,

openldap-2.2.18 + postgresql-7.4.1 + unixODBC-2.2.10
Solaris9, SUNW,Sun-Blade-100
1000 entries, like:
	dn: cn=xxx(0-1000), o=xxx,c=xx
	objectClass: top
	objectClass: person
	objectClass: inetOrgPerson
	cn: xxx(0-1000)
	sn: xx
	description: This is performance description
	telephonenumber: (0-1000)
	title: TEST
	userpassword: xxxxx
	givenname: xxxxx

No problem happens on ldapadd, ldapmodify and ldapsearch, 
but when I run
ldapdelete -h xxxx -p xxxxx -D "cn=xxxx,o=xxx,c=xx" -w xxxx
cn=xx,o=xx,c=xx
ldap_delete_s: Can't contact LDAP server

the SLAPD log shows 
------------------------
...
<==backsql_get_db_conn()
==>backsql_dn2id(): dn="cn=xxx,o=xxx,c=xx"
id_query "SELECT id,keyval,oc_map_id FROM ldap_entries WHERE upper(dn)=upper(?)"
<==backsql_dn2id(): id=998 keyval=1000 oc_id=1
==>backsql_count_children(): dn="cn=xxx,o=xxx,c=xx"
children id query "SELECT COUNT(distinct subordinates.id) FROM ldap_entries,ldap_entries subordi
nates WHERE subordinates.parent=ldap_entries.id AND upper(ldap_entries.dn)=upper(?)"
<==backsql_count_children(): 0
Segmentation Fault (core dumped)

Checked CORE, it showed:
------------------------
...
signal : SIGSEGV        fault pc: 0xff0b347c     libc.so.1:strlen+0x80
platform: SUNW,Sun-Blade-100
(scrash) t
...
[psr]0xfe401007 [ y ]0x00000000 [wim]0x00000000 [tbr]0x00000000
[pc ]0xff0b347c   libc.so.1:strlen+0x80 ld      [%o1], %o2
[npc]0xff0b3480   libc.so.1:strlen+0x84 add     %o1, 0x4, %o1
[ 1] libc.so.1:strlen+0x80     ld      [%o1], %o2
 (0xc6ba8,0x0,0xfdbfe770,0x0,0x0,0xf5660)
[ 2] libc.so.1:vsnprintf+0x5c  call    _doprnt (ff13e19c)
 (0xfdbfe7e0,0x1000,0xc6ba8,0xfdbff840,0x4c,0x53)
...
[10] 0x7fe70
 (0xddc00,0xfdbffd60,0x40,0xfdbffc60,0x7fa6c,0x0)
[11] 0x3cd34
 (0x12ff90,0xfdbffd60,0xfdbffd5c,0x0,0x2a8c4,0xe3d38)
[12] ldapdelete:ldap_str2syntax+0x114 st      %g1, [%i2]
 (0xfdbffe10,0x12ff90,0xff040600,0xfdbffe0c,0x40,0x0)
[13] 0x8b5b8
 (0xf1e80,0x0,0x0,0x0,0x0,0x0)
[14] libthread.so.1:_lwp_start nop
 (0x0,0x0,0x0,0x0,0x0,0x0)
(scrash)
------------------------

Did somebody meet such problem?

regards
Pu