Domino access through internet & RSA

I have a configure lotus mail access in such a way that users will first access our company portal i,e www.abc.com , click on to a mail icon so that it takes the user to his domino mail box via the internet. Before accessing the domino mail box, RSA encryption needs to be used for authentication.

Please guide me in configuring such a setup. Is there any sites where I can find some resources ?