Add-in encryption module to Netscape

Hi, Lurking here for quite some time until now a real problem has come up and I need help here. I'm not in the US of A and the Netscape commerce server that my employer recently purchased has only 48bit key (as told by the salesman). My question is whether it is possible to add-in my own security module (RSA) and secondly, how difficult is it? The salesman cannot answer me. Thanks a lot.