SI client with ToA/SI expansion pack?

[Totyn]

I bought the ToA/SI expansion a few month ago and havent figured out a way to play with the SI client yet. I only have a ToA client in my daoc folder and i have no idea if it is even possible to play SI client. Have somebody been able to do that? Really annoying when going to RvR and i lag to hell and then i have to run with classic daoc wich sucks because there is no windowed mode.