This is not really a problem yet, but a bit of a concern. So, I set up and render a scene from Maya at 24 frames, I have import and comp size set to 24 frame in after effects. The length is correct, but when I render the image sequence out and back in, it's only 12 frames. Watching a scene render out, I see after effects skip frames. Is it a setting somewhere?
Video was rendered using AE CS4 (v9.0.2) in QT (v7.6.2) at 23.976 fps.
When re-imported into AE, the footage was correctly interpreted as 23.976. However, when this clip was rendered out again (from 23.976 comp), the end result is such that there are 24 physical frames a second but many frames were skipped (by repetition). Therefore, you have a 23.976 fps video but with a motion effect of half that frame rate.
This can be solved by opening up the initially rendered file in QuickTime, and re-export using QuickTime. Only then if you re-import the footage into AE CS4 that the render will be correct.