AAM

Just taking a stab at this... I think that if on the http profile, you enable Insert X-Forwarded-For, that will insert that info into the http headers. You then would have to configure you imparva to extract/use X-Forwarded-For info from the headers. I have no direct experience with it in this direction. I have only used X-Forwarded-For to load-balance to the back-end servers (iRule). Hope this helps.