I have a development site set up here: powerstore.i-cre8.com/ which is covered by my wildcard SSL certificate
A couple of points:
1) The checkout page does not automatically trigger the SSL cert see this screenshot:
this is VERY BAD
2) You forward to an unframed 3D Secure Page
I would prefer to see this in an iFrame so that the customer doesn't think they have left my site and possibly get confused and abandon the checkout process. Work to the lowest common denominator !
3) The fact that the checkout process is not covered by the SSL cert gives this error
4) Other than the above the 3D Secure process worked