aac & ripping mono tracks

[Tony Wilson]

I set my prefs to auto rip in stereo/mono, but the cds that are labeled 
as mono recordings still rip in stereo. Is this because of faked stereo 
applied in the production of the cd or just iTunes falling down. Will I 
have to change the setting manually everytime. And does anyone know the 
year stereo began and could I safely rip every track from before that 
year in mono even if the imitation stereo was used.

Thanks;
Tony