No, For the simple fact that it is better to integrate jBPM with a usermanagement system, which might contain an ldap server, than directly with an ldap server (AD, OpenLDAP, Oracle etc...)

There is a jira issue to look into integrating with the portal usermanagement, which in turn could (should?) be come a separeted component.

OTOH, if you know a little ldap, and look into the identitymanagement code, it is not to hard to do yourself.