Secure www to Secure NON www

None of the server side SSL should handshake stuff will be visible to the client, unless the BIG-IP and server cannot successfully negotiate SSL. The error that the client is seeing is most likely because the subject of the certificate presented to the client during its handshake with the BIG-IP is not that same server name that the client asked for. There's very little you can do to mitigate this other than getting a server certificate that matches the name the client is using.