check for user existence with login

Hi,

Is there a way to (easily) check for the users existence in the Bonita DB when logging in?

I validate the users password to LDAP when logging in, but this is no guarantee that the user exists. Since I get all kinds of errors when I let these users log in, I want to prevent that.

I was thinking to add a second validation using the standard loginModule (org.ow2.bonita.identity.auth.BonitaIdentityLoginModule), but that requires a password which I don't have.

Is it perhaps possible to use this with a standard password like for the RESTserver example in jaas-standard.cfg?