https, certificates and SSL

I want to use IS to access multiple clients with different certificates using https.

The only way to do this is by using the setKeyAndChain/clearKeyAndChain.

If I only had one client I would use the outbound SSL certificates. By using this the IS mantains a SSL session between invocations, in order to be most efficient?

Using setKeyAndChain/clearKeyAndChain, the IS is allways destroying the SSL session? Isn’t this little efficient? how to overcome this problem? how to maintain a SSL session between invocations to overcome the ssl handshake lost time?

Thanks in advance,