ASIO or multi-channel WDM drivers for surround mixing

I use Cakewalk Sonar which allows you to do surround sound mixing. This is generally done by assigning different analog outputs for the all the surround channels. I was hoping to get a Callisto as an easy way of routing the surround sound (avoiding analog). That is, assign the surround outputs appropriately and have this sent digitally as DTS to my receiver. Do you have any idea if this will work? Are there ASIO drivers or multi-channel WDM drivers with outputs that I would be able to select in Sonar (e.g. individual L/R front, L/R surround, and center/LFE outputs)? Thanks.