Check the deployment_update.log (something like that) for errors. You may have to setup the ldap auth configuration again in blasadmin.
Well when I ran a show ldap all:
I found that the TrustStore entry was missing the path to the ldapTrustStore.pkcs12 cert.
I added this info back, rebooted, and all is well. LDAP users are authenticating into BladeLogic.