ldapwhoami -D vs -U

Question

I have an LDAP user with this schema:

dn: uid=portal,ou=Special Accounts,dc=example,dc=com
objectClass: inetOrgPerson
objectClass: organizationalPerson
objectClass: person
objectClass: top
sn: portal
cn: portal
uid: portal

Can anyone tell me why this would work:

ldapwhoami -h yorktown -U portal

but this:

ldapwhoami -h yorktown -D "uid=portal,ou=Special Accounts,dc=example,dc=com"

results in

ldap_sasl_interactive_bind_s: Invalid credentials (49)
        additional info: SASL(-13): user not found: no secret in database

Solution

I guess -D is for simple authentication and -U is only for SASL. When I do ldapwhoami -h yorktown -D "uid=portal,ou=Special Accounts,dc=example,dc=com" -x it works fine.

Comments

[MastaJeet]

What's your sasl-regexp in slapd.conf (if you have one)? What SASL authentication mechanism are you using?