Custom Payment

Hi,

We don't use any of the payment providers and I wish to use my own, (Cardsave online).

I have read through a number of posts in the forum and the blog section (http://www.sitefinity.com/blogs.aspx?BlogCatID=Ecommerce) but am still unable to determine if I can implement a custom payment processor with 3D Security authentication.
For those that are not familiar, it is basically an extra step in the payment process that occurs after submitting card details, and involves asking for 3 characters of a pre-agreed password (see attached image).

Has anyone been able to do this and if so, provide me some help in order to achieve this myself?

Thank you

I've just worked out a solution for this myself, using SagePay:  stackoverflow.com/.../implementing-3d-secure-with-sitefinity-ecommerce