And it'll probably load faster from home, too...
The newest CAC certificates (CA 24) don't always work with the Mac OS X 10.5/Leopard and might need a bit of work on your part to work with 10.6/Snow Leopard. Militarycac.com explains all of that and it's also good DIY tech support.
There was a recommendation for a piece of software that streamlined the process for ~$30...
There was another option on there (for Snow Leopard/10.6) with either a freeware or beta version (but free either way) that I tried and it worked for me. YMMV, use at your own risk, etc.
As for security "features" and their "upgrades," when I wonder why the upgrade is somehow better, for some reason I always I think of this:
That's the weird thing about Windows 7 (and documented on Jim's recommended site). To get into Sharepoints, you have to use your email cert, even though you're supposed to use your security cert. But to get into SHARP, you still use your security cert. Neither worked for me when it came to E-Leave.Does SHARP use the email certificate or the identity certificate? I know that NMCI really wants the email cert and balks at your identity cert.