Have you tried using the 'java.naming.security.principal' and 'java.naming.security.credentials' in your properties file? They worked for me (thank you for the hints).
Also, what is the correct configurations to get just the CN for a user's groups (e.g. just 'user', or 'admin') into the task.OrganizationalEntity table? Below is a section of my current configuration, which results ininserting the entire string 'CN=admin,CN=Users,DC=...' as the 'Group' id. Thanks in advance.
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# Filter that will be used to search for user information,
# usually will contain substitution keys {0} to be replaced with parameters
# (mandatory)
ldap.user.filter=(sAMAccountName\={0})
# Attribute name of the user id in Active Directory
ldap.user.attr.id=sAMAccountName
# Filter that will be used to search for group/role information,
# usually will contain substitution keys {0} to be replaced with parameters
# (mandatory)
ldap.role.filter=(sAMAccountName\={0})
# Filter that will be used to search for user group/role membership information,
# usually will contain substitution keys {0} to be replaced with parameters
# (mandatory)
ldap.user.roles.filter=(sAMAccountName\={0})
# Attribute name of the group/role id in Active Directory
# (optional, if not given 'cn' will be used)
ldap.roles.attr.id=memberOf
# User id a DN, instructs the callback to query for user DN
# before searching for roles (optional, default false)
ldap.user.id.dn=true
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