What, exactly, do you want to use this for ?
If you want actual SSL to be “emulated” by scripts, don’t bother; by the time your request would hit your server side script, it would be too late to start a proper SSL session.
If you just want the appearance of security, don’t bother. Either use SSL/TLS, or don’t encrypt the transport layer.
Shared SSL certs are icky, though should theoretically be possible; many browsers do not support it in the correct fashion, though. I wouldn’t hold my breath on DH support for these, though you might want to suggest it in their suggestions panel.