Yeah, like this:
AddDamageType("RocketDirect", '<bitmap:add-ons/Weapon_Rocket_Launcher/CI_rocket> %1', '%2 <bitmap:add-ons/Weapon_Rocket_Launcher/CI_rocket> %1',1,1);
AddDamageType("RocketRadius", '<bitmap:add-ons/Weapon_Rocket_Launcher/CI_rocketRadius> %1', '%2 <bitmap:add-ons/Weapon_Rocket_Launcher/CI_rocketRadius> %1',1,0);
Notice you get the Name rocket Name when you hit someone with a rocket and the Name (rocket) Name when the rocket explodes close to them