New oils with less ZDDP.
Most every premium oil I have every run across has both gasoline and diesel engine ratings on it. So, I would think that you would be prety much getting the same stuff if you purchased oil marketed for gas engines that has the same diesel rating as you would an oil marketed as a diesel oil.
For Example: From the Mobil web page;
Mobil Clean 7500 10W -30 provides excellent all season protection in a wide variety of vehicles. It exceeds warranty requirements for gasoline engines where an API certified oil is specified. It meets:
ILSAC GF-4 (API Certified - Starburst)
API SM/SL
GM 6094M
The Requirements for Diesel-Powered Vehicles where an API CF or API CD is Recommended