How to get TLS working on LDAP, NSA3600?

Hi,

I have a new NSA3600, trying to get LDAP auth working (for the L2TP VPN). When I disable TLS, everything under the LDAP and RADIUS windows tests OK.

As soon as I check the Use TLS box I get LDAP communication error.

I have a CA certificate from the domain controller installed on the NSA and LDAPS tests OK with the ldp.exe tool.

What else can I change/try?

Thanks