Client certificate

Hi ,
I am trying to implement client authentication based on client
certificates.

I want to throw up an error message to the "user/browser" in case client
certificate is invalid.

What I got was that "The page cannot be displayed" error if an
invalid(expired one) client certificate is sent and I see the following
in the logs.
==========================================================
[Tue Nov 14 16:52:53 2006] [info] [client 14.64.53.89] client stopped
connection before rflush completed
[Tue Nov 14 16:52:57 2006] [error] mod_ssl: Certificate Verification:
Error (10): certificate has expired
[Tue Nov 14 16:52:57 2006] [error] mod_ssl: Re-negotiation handshake
failed: Not accepted by client!?
[Tue Nov 14 16:52:57 2006] [error] mod_ssl: Certificate Verification:
Error (10): certificate has expired
[Tue Nov 14 16:52:57 2006] [error] mod_ssl: SSL error on writing data
(OpenSSL library error follows)
[Tue Nov 14 16:52:57 2006] [error] OpenSSL: error:140890B2:SSL
routines:SSL3_GET_CLIENT_CERTIFICATE:no certif
icate returned
[Tue Nov 14 16:52:57 2006] [info] [client 14.64.53.89] client stopped
connection before rflush completed
========================================================================
====

Ideally , I would like to be able to find that the client certificate
has expired using the "SSL_Client....." variables and be able to give
user some error message.

Is it possible?

Thanks,
Vishal

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