Diaqueen Transmission Oil is the OEM 75W85 GL-4 transmission fluid that Mitsubishi calls for in the 03-06 Evolution's service manual. Diaqueen is recommended for 5-speed Evos, and is required in the 6-speed Evo MR. Diaqueen Transmission Oil and Diaqueen LSD Oil are not the same thing and are not interchangeable.
Mitsubishi's fluid specs for the 03-06 Evolution 8 & 9:
5-SPEED TRANSMISSION: 2.8L Diaqueen 75W85 or 3qt Red Line MT-90
6-SPEED TRANSMISSION: 2.2L Diaqueen 75W85 or mix 1.6qt Red Line MTL & .7qt Red Line MT-90
TRANSFER CASE: .6L of Diaqueen LSD
REAR DIFF: .55L Diaqueen LSD or .58qt Red Line 75W90